The hickory nut has not reached the popularity of the pecan, although

the hickory contains more protein and slightly less fat, carbohydrates,

and calories per pound than the pecan. Where the pecan does not fruit,

the better hickories, which are hardy, fill the need. The named

varieties are good and trees are available from some nurserymen. The

propagators have developed a few new crosses but man is far behind

nature in this work. The many new seedling trees scattered all over the

regions where the hickory grows require only propagation and

distribution for wider acclaim.

The development of a new hickory is a long-time process, yet may be

hastened by first planting the nuts for new seedlings and when the

growth is mature to bud or graft the seedling on large rootstocks. When

old trees have been top-worked it is only two or three years' time until

the fruit develops and, if worthy of propagation, much time may be saved

by this method.

Most of the hickories have either 32 or 64 chromosomes, except pecan

which varies from 20 to 24 to possibly 32. The chances of making

suitable crosses between the pecan and hickory are most difficult yet it

appears that these chance crosses result from time to time as in the

hican through natural cross pollination.

How extensive will be the plantings of the hickories is yet to be

determined but it is a known fact that many people, especially north of

the route of Federal Highway 40, prefer the hickory to the pecan. This

may be due to the fact that from childhood the hickory was the local

fruit. The fruit and tree hold great promise for the future. If the

hickories are to be of commercial importance, the work must be done by

all concerned and not left to a few eager individuals to carry on the

work alone.

MR. MACHOVINA: Mr. Chairman, members of the Association, I hope you will

bear with me if I run 30 seconds over. Perhaps I had better point out

that my training is that of an engineer and not a botanist, hence this

report on the Merrick tree is that of a layman. I have not bothered to

go into detail on the various features of the tree, such as leaves,

buds, and so forth, because I have slides which you will see afterwards.

The Merrick Hybrid Walnut

P. E. MACHOVINA, _Columbus, Ohio_

The Merrick hybrid walnut is a natural cross between Persian and black

walnut and is distinguished from most other such hybrids by the good

crops it usually bears. The tree is located in Rome Township, Athens

County, Ohio, on property owned by Mr. M. M. Merrick a farmer and fruit

grower.

In August, 1950, Mr. Merrick first described his "English" walnut to the

writer and arrangements were made to view the tree. Most striking at

first sight was the large crop of nuts. The general outward appearance

of the tree suggested it to be pure Persian; however, upon closer

examination, mixed parentage became evident. As a hybrid, the tree's

history was a matter of interest and the owner was happy to supply what

information he could.

Mr. Merrick purchased the property on which the hybrid is located, in

1921. A few years prior to this, the previous owner had planted six

Persian walnut trees obtained from a nursery in northern Ohio. These

young trees bore their first crop of nuts during Mr. Merrick's first

year of ownership. It is known that the nursery owners were also

proprietors of a commercial Persian walnut orchard located in the

vicinity of Niagara Falls. With this combination of date and orchard

location, it seems not illogical to presume that the six nursery trees

were of the Pomeroy strain. From Mr. Merrick's description of the nuts

produced by these trees, they appear to have been two each of three

different grafted varieties. In the early nineteen-thirties, Mr. Merrick

planted several nuts from the Persian trees and raised a number of

seedlings. One of these seedlings, transplanted to its present location,

is the subject of this discussion and is presumed to be a cross between

one of the six Persians and a native black walnut. During the late

nineteen-thirties, all of the trees, Persians and seedlings, with the

single exception of the existing hybrid, were killed by an unusually

hard winter.

The Merrick hybrid walnut, now about 20 years of age, is an extremely

vigorous and healthy tree. Its height is between 55 and 60 feet and its

spread nearly as great. Trunk diameter is at present about 12 inches at

breast height. The location of the tree is very favorable, being near

the crest of a high ridge and with protection from the northwest by the

house. A chicken yard is near and the kitchen drain empties close by to

supply moisture.

In nearly all aspects excepting the nut itself, the tree favors its

pistillate parent. This is evidenced by the general shape of the tree,

by the texture and color of the bark of limbs and twigs, and by the

shape and color of the leaves, the buds, the flowers, and the nut hull.

Hybridity is indicated by the (usually) eleven leaflets to the leaf

stem, by the nut, and in the disintegration of the hull which, after

falling, quickly changes into a most disagreeable, dark-brownish,

semi-liquidlike mess. The nut itself is much more like a Persian walnut

in appearance than a black walnut. The shell surface is slightly rougher

and somewhat darker than most Persian nuts. The suture of the Persian

parent is prominent. Black walnut parentage is exhibited by the thick

shell, the interior configuration and in the flavor of the small kernel.

Nut size varies somewhat with diameters ranging from 1 to 1-1/4 inches

and lengths ranging from 1-1/4 to 1-1/2 inches.

The bloom, which is strikingly like that of pure Persian trees, is

always profuse and precedes that of the surrounding native black walnuts

by a week or two. In the two years during which the writer has observed

the tree, the greater part of the staminate bloom has preceded the

pistillate by several days. This was noticeably the case during the

current year, and either this, or the rainy weather, has resulted in a

small set of nuts which the owner states to be unusual. During the years

observed, the tree appeared to be self-pollinating.

It is recognized, of course, that the Merrick hybrid is worthless as a

producer of edible nuts. The possible value of the tree lies in

opportunities it offers in being the forbearer of more worthwhile

progeny. We know of the vast possibilities in hybridization. We know of

the difficulties involved in obtaining nuts from controlled crosses

between Persian and black walnut trees; and we know that seedling trees

raised from the nuts of such crosses are almost always sterile. The

Merrick hybrid, yielding good crops, offers possibilities both in

crossbreeding and in the raising of seedling trees from the nuts of the

tree itself. In the latter connection, Drs. Crane and McKay, of the

U.S.D.A., requested several pounds of Merrick nuts for planting purposes

this spring. The writer himself planted five such nuts, of which four

germinated. Of the four trees, one died early in the season, while the

remaining three have thrived. The heights attained by the three

remaining trees thus far this season are 1, 2, and 3 feet, respectively.

These trees have the general appearance of young Persian seedlings.

The only crossbreeding attempted thus far ended in failure when a storm

destroyed most of the bags prior to application of pollen. Persian

pollen was used on the few bloom remaining covered but, unfortunately,

no nuts were set. The experiment will be continued. Also, the Merrick

will be topworked onto producing walnuts, both Persian and black, in the

hope of obtaining nuts from which interesting and perhaps better second

generation hybrids can be raised.

An interesting point of conjecture on which to terminate this report,

and one to which nut experts will likely give little credence, may be

found in a statement made by Mr. Merrick and vouched to by Mrs. Merrick.

The statement is to the effect that the nuts borne by the Merrick during

its early years, that is, prior to the time the adjacent Persians were

killed, were of much better quality, being more like Persian walnuts

both in appearance and in flavor. We've heard of "pollen influence" with

chestnuts. Did it occur here?

TUESDAY AFTERNOON SESSION

Producing Quality Nuts and Quality Logs

L. E. SAWYER, _Director, Division of Forestry and Reclamation, Indiana

Coal Producers Association_

I was trained as a forester and having worked at the profession for

nearly thirty years, my first thought of trees is for their utility in

building or in cabinet work. In school we were taught that the fruit of

forest trees was a by-product. Its economic importance was not

emphasized nor was the possibility of establishing stands of some

species specifically for the production of their fruit.

Through the years the value of the nut crop from some species has

increased so that the fruit is now the primary crop and any wood

materials that may be derived are the by-product. This production of

valuable food and necessary materials of high quality for the building

of quality furniture and interior finish is a combination that will work

well together.

Black walnut, the most highly utilized of any of our native timber for

furniture, veneer, and cabinet work is becoming increasingly more

difficult for the mills to obtain in larger sized logs. Native chestnut,

almost completely destroyed in our timbered areas by the chestnut

blight, is in demand for interior finish. Pecan, which has had only a

limited use in the past, is now enjoying a market for the manufacture of

flooring.

The production of nuts from plantations or orchards of these three

species will no doubt produce greater economic returns for many years

after the initial planting than could be derived from the sale of the

trees for the wood they contain. There will come a time in the life of

any tree when it is no longer a profitable producer and should be

replaced by a younger, more thrifty tree. When that time comes, the tree

to be removed will have no economic value unless it contains products

that industry can use. With the thought in mind that the wood from the

tree is to have some future economic value the trunk of the tree should

be kept free of all limbs to a height of about nine feet above the

ground. The development of a large spreading top above that point will

be desirable for nut production. The space below that top will give

ample head room for maintenance work in the orchard and that clear

length of trunk will produce a high quality log eight feet long. That is

the minimum standard length normally used by the lumber industry. Some

shorter lengths are utilized by the veneer industry but those lengths

usually command a lower unit price.

The production of figured walnut could be combined with the production

of one log per tree but it would take several more years to bring the

trees to nut producing age. Mr. Wilkinson has successfully demonstrated

that the figure of the Lamb Walnut does carry over through a graft or

bud.

A double budding operation should not be difficult to perform. It would

simply consist of budding the figured stock on the root at as low a

point as possible, then when the figured growth has reached sufficient

height, of budding again to the desired variety for nut production. This

procedure would no doubt require a few additional years before the first

crop of fruit would be harvested but it would produce an extremely

valuable log when the tree is finally cut.

I would be remiss in my present job if I did not bring the revegetation

program of the Indiana coal stripping industry into the discussion. That

industry produces over fifty percent of the coal mined in Indiana today

and is recovering coal that could not be mined by any other means.

In driving to Rockport many of you no doubt passed by areas of newly

mined land, rough, barren desolate looking areas with no vegetation.

They have the appearance of complete desolation and give the impression

that those lands are forever lost. In that same vicinity you no doubt

passed plantations of pine, or mixture of pine or Locust with our native

deciduous species. Those too were mined areas that a few short years ago

were just as desolate in appearance as the bare areas you saw. These

plantations are the direct result of a reclamation program started by

the members of the Indiana Coal Producers Association, a program that

has attracted national attention.

The first record of an attempt at the reclamation of coal mine spoil is

here in Indiana. In 1918, the Rowland Power Company, now owned by the

Maumee Collieries Company, planted peach, apple and pear trees on mined

land in Owen county. The records show that for a period of years the

trees thrived and were good producers. Then, because the topography was

rough and no spraying was done, disease and insects took their toll of

the peaches and apples. Seedlings of the original apple and peach tree

still grow on the area. The original Kieffer pear trees still stand and

produce large crops of fruit.

In 1926, the larger, more far sighted companies began a definite program

of reforestation of their mined lands under the direction of Ralph

Wilcox, at that time assistant State Forester and fortunately our State

Forester today. That voluntary program was carried on until 1941 when

the Indiana Coal Producers Association, the Association of the mining

companies, sat down with representatives of the Indiana Department of

Conservation, representing the state, and the Indiana Farm Bureau,

representing the people, and drafted a bill which was enacted into law.

This law required each company to obtain a permit from the state to

operate and required that each company revegetate an area each year

equal to 101% of the area they had mined. To insure compliance, a bond

was required. This law remained in effect for ten years. In 1951,

representatives of those same groups again sat down together and drafted

several amendments to the original act. Some grading is now required

where areas lie adjacent to public roads. Access roads must be provided

and areas to be devoted to pasture must be graded so that they can be

traversed with agricultural machinery.

Under this program, sponsored by Industry, the Farm Bureau, and the

Department of Conservation, 79% of the area that has been mined to date

has been successfully revegetated. The remaining 21% is a natural lag

and represents lands newly mined or areas that have not weathered to the

point where they will support revegetation. The demand for recreation

lands and home sites where water is available is constantly increasing.

At least 13% of the revegetated area is now being used for public

recreation or for home sites. Near the more heavily populated sections

the price commanded by mined territory containing good lakes often

exceeds the value of the land before it was mined.

These lakes, formed in the final cuts and in low lying areas of the

strip mines, furnish the only clean, clear water available for public

recreation and fishing in the south western part of the state.

The reforestation being carried on under the reclamation program

consists of planting several species of pines, as well as a large

variety of our native deciduous trees. The older plantations are being

used as a guide as the research started in the last eight years has not

progressed far enough to give conclusive results on many points. Until

the last few years the Agricultural Experiment Station has devoted

little or no time to the problem of reclaiming strip mine spoil. The

area of the state that is involved, less than 1/4 of 1%, has been too

small to justify the use of their limited funds. However, since funds

have been made available to that Station, through the Industry, to

establish research fellowships, the Station has given whole hearted

cooperation. The information being obtained through these fellowships

and through work being carried on cooperatively with the Central States

Forest Experiment Station is going to answer many of the questions on

reclamation we have been confronted with.

Included in our reforestation has been a liberal scattering of black

walnut. A breakdown of species is not available on much of the earlier

work but since 1940, when accurate records have been maintained, we have

planted 239,000 black walnut seedlings or seed. Initial survival is not

high, averaging only about 50 percent but we still have a general

distribution of seed trees that are providing a source of seed for

natural reproduction. Trees from plantings made in 1927 to 1934 have

grown well and we now have walnut trees over 10 inches in diameter and

60 feet in height. The average for all areas would probably not exceed 5

inches but individual trees have made remarkable growth. These trees are

only seedlings, but they are bearing heavily and their fruit is sought

by the local people.

In 1946 and 1947, budded stock of walnuts and pecans and seedlings of

Chinese chestnut were obtained from Mr. Wilkinson and were set out on

six selected areas. A wide variety of sites were picked and a wide

variation in both survival and growth has been obtained. No special

treatment was given the areas where the trees were to be planted nor

were the trees mulched or watered after planting. Even under these

rugged conditions we have a survival of over 60 percent of all trees.

The walnut trees now range from 5 to 12 feet in height and the pecans up

to 6 feet. The chestnuts vary in form from low spreading plants 4-1/2 to

5 feet in height and as much as 8 feet across to well formed trees 8 to

10 feet tall. Pruning on all three species to produce a clear butt log

has been started.

Pasture seeding on areas high enough in available lime to support

legumes is following a pattern laid down by three years of graduate

study, financed by the Indiana Coal Producers Association, at Purdue and

by work done by the Illinois Agricultural Experiment Station under a

similar arrangement with the Illinois Coal Strippers Association.

Unfortunately, we have only a small portion of the spoil area in Indiana

that is suitable for the development of improved pasture. Not over 10

percent of the area mined to date is good enough and that percentage

will decrease. Modern operations are deeper than the early ones and are

exposing more hard rock and shale. Fortunately, most of these areas can

be reforested after three or four years. In exceptional cases less than

5 percent of the area mined the exposed materials contain large amounts

of sulfides. These break down into acid that in some cases require ten

to twelve years to leach out before revegetation can be undertaken.

The fact that these stands of trees established on raw spoil will

produce merchantable timber has been proven. In 1951, an area was clear

cut at the Enos mine in Pike county. The pines on this tract were

planted in 1933-34. The products from that cutting, peeled posts and

poles, were sold to the Indiana Wood Preserving Company at the rate of

$335.59 per acre. An increase in value of $16.48 per acre per year.

Pasture, forests and fishing are not the only products. Game of all

varieties is abundant in the worked out areas. One of the largest herds

of white tailed deer in the state, now referred to as the strip mine

herd, is located in northern Warrick and southern Pike counties. In the

Indiana deer season of 1951, the first open season since 1893, the

second largest recorded kill came from the strip mine herd. The

Pitman-Robertson report of the Division of Fish and Game carries the

following comment on deer from that area. "The superiority of the

diversified range of the strip mine herd was reflected in above average

weights and measurements in most age classes."

From the evidence at hand, there is every reason to believe that most of

the mined area will again be highly productive forest land. It has

completed the entire cycle of land use. Originally it supported

magnificent stands of hardwood timber. This timber was cut and the lands

devoted to farming. Poor management and erosion soon depleted the supply

of top soil and many areas were abandoned to broom sedge, blackberries

and gullies. Because it was close enough to the surface the coal has

been removed and the areas replanted to many of the same species of

trees.

With this reestablishment of the forest cover and the creation of the

lakes in the final cuts, we can again have our forest resource combined

with fishing, hunting and other forms of outdoor recreation, some areas

of pasture and, I believe, others that can be profitably devoted to the

production of nut crops and the by-product of quality logs for the

veneer and lumber industry.

PRESIDENT MacDANIELS: If you ever think you are going to sell your logs

for veneer or lumber, don't nail hammocks or other things on the trees.

The metal is very soon buried and causes no end of difficulty. We will

go to the next paper, which is, "Colchicine as a Tool in Nut Breeding,"

Mr. O. J. Eigsti, Funk Brothers Seed Co., Bloomington, Illinois.

MR. EIGSTI: Three years ago this project was conceived in a discussion

between Mr. Best and myself. Then during the two-year period, all I did

was turn over some Colchicine to Mr. Best. Mr. Best took the material,

treated the trees and performed as well as any graduate student I had

ever graduated in the 13 years that I was in university work. It is

through his fine cooperation that we are able to start this project, and

I look forward to this developing into a rather important nut breeding

venture. But as you all know, it will take a long time. I have this

paper written. It's only four pages double-spaced.

Colchicine for Nut Improvement Programs

O. J. EIGSTI and R. B. BEST, _Normal, Illinois, and Eldred, Illinois_

Colchicine (1, 2) as a plant breeders' tool is universally well known.

Only limited use has been made of this technique for nut improvement.

Early work was started by Dr. J. W. McKay, a member of the N.N.G.A., but

numerous other problems demanded his attention and the Colchicine

project was not carried to final completion. Other reports are at hand

from Sweden and Japan but these results do not shed direct light on the

problems under discussion today at Rockport, Indiana.

Colchicine, acting on cell-division, ultimately causes a doubling of the

number of chromosomes within those cells in contact with the substance

at the time of division. Such changes are transferred to succeeding

generations by the hereditary chain familiar to plant breeders. Several

species of nuts are among this class of plants with doubled chromosomal

numbers, however, such duplications occurred in nature. A report on this

phase was given at a recent meeting of the N.N.G.A. Therefore such

excellent nut producing species as the pecan are naturally doubled

types, called polyploids. We find numbers such as 32 representative of a

polyploid situation.

Since colchicine is effective in doubling the chromosome number and that

variations in chromosome number exist among species, the authors planned

a series of experiments to determine the best methods of applying

colchicine toward a nut improvement program. Seedlings of pecan were

available and out of this experience a schedule is submitted that may be

of use for other members of this association confronted with particular

problems applicable to colchicine techniques.

The most satisfactory schedule for doubling the number of chromosomes is

given in a number of steps as listed below.

1) Select expanding vegetative buds in the earliest stages of

development.

2) Use seedlings or branches from mature trees.

3) Prune leaves and probe to the growing cone without damage to tissue.

4) Pack a small wad of cotton into the terminal point.

5) Soak this cotton by dropping .2% aqueous solution of colchicine on

same.

6) Add glycerine to cotton to improve penetration of colchicine.

7) Place drop of colchicine on cotton morning and evening for four days.

8) Remove cotton wading from bud on 5th day.

9) If sufficient tests at hand, allow cotton to remain on some buds.

10) Try for at least one hundred buds treated.

11) Observe growth during first season and also next season.

12) If treated bud dies, watch for growth among lower laterals.

13) Evidence of changes appears in the new leaves, darker, thicker,

greener.

14) Conclusive evidence of doubling rests with microscopic and

anatomical analysis which is a task for trained technicians only.

The above procedures are suggestions for a start and everyone will wish

to make changes suited to his particular needs. The concentration of

colchicine need not be exact as in an analytical experiment in

chemistry. One gram dissolved in 500 ml. water is an adequate and a

sufficiently careful measurement. The local pharmacist or physician is

well acquainted with colchicine in the practise of medicine since this

drug is a standard for gout.

Effective use may be made from two specific areas of plant breeding.

First, doubling of chromosomes changes sterile hybrids into fertile

individuals. This is a promising field and whenever such hybrids are

discovered, efforts should be made to apply the colchicine technique.

Second, doubling of the chromosome number makes possible hybridization

of individuals heretofore unsuccessful in such effort. In both instances

germ plasm of wide genetic difference is incorporated into a new

propagating breeding stock. In the case of the sterile hybrid

transformed into fertile individuals, no counting of chromosomes is

necessary because restoration of fertility is evidence of changes in the

chromosomal makeup. However, the second type of experiment requires

microscopic analysis.

There are a number of fundamental research problems in the plant

sciences associated with the treatment of plants with colchicine. From

horticultural subjects such as the apple,(3) pear, cranberries,(4) and

grapes, it is obvious that periclinal chimeras will be of prime

importance in analysis of results in treatment of nut trees. Following

the treatment of a growing point with colchicine the outer layer of

cells may be doubled by colchicine but the lower layers may remain

unchanged. Or a reverse of this situation may obtain, and even other

types. Since the formation of pollen takes place from a certain layer it

is very important that such specific layers are changed. The course of

plant breeding can be altered by these kinds of changes. To our

knowledge, no investigations of periclinal chimeras have been made with

nuts, following treatment with colchicine.

Specific experiments were conducted at Eldred, Illinois in the spring of

1951 with seedlings of pecan. The cooperation of the R.B. Best Farms and

Nut Plantation made this project possible. Several types of treatment

were tried. Out of this experience the above schedule listed in 14 steps

was developed. Other details may be obtained by contacting the authors

direct. Observations of the new growth in 1951 and 1952 were made and

the shape of leaves, color, texture and general appearance suggest that

doubling of chromosomes has been induced. Up until the present time, no

microscopic analysis has been made but this is a contemplated step and

facilities are at hand to complete this work.

While this paper is not a completed research, the authors hope that the

presentation of technique will aid and stimulate interest in this new

approach to nut improvement. In such instances where certain members may

have a particular problem such as a true hybrid-sterile as a result of

hybridity, it is hoped that the suggestions given in the above pages may

lead into a new field of improvement. There are rewards in store for the

plant breeder willing to master this new technique, but the mastery

requires careful study and diligent work.

Literature Cited

1. Eigsti, O. J. and Dustin, P.--Colchicine Bibliography. Lloydia 10:

65-114. 1947.

2. ----, ----.--Colchicine Bibliography. Lloydia 12:185-207. 1949.

3. Dermen, H.--Ontogeny of tissues in stem and leaf of cytochimeral

apples. Am. Jour. Bot. 38:753-60. 1951.

4. Dermen, H. and Bain, H. F.--Periclinal and total polyploidy in

cranberries induced by colchicine. Proc. Am. Soc. Hort. Sci. 38:

400. 1941.

PRESIDENT MacDANIELS: The Resolutions Committee for this meeting is:

John Davidson, chairman, and Dr. Rohrbacher working with him. If you

have anything in mind that should be brought up in the resolutions, see

one of these two men.

The next paper is:

An Early Pecan and Some Other West Tennessee Nuts

AUBREY RICHARDS, M.D., _Whiteville, Tenn._

MR. RICHARDS: There came under my observation in the latter part of last

summer a seedling pecan tree growing in the city limits of my home town.

It seemed that this tree had been growing unnoticed for possibly 50

years, judging by the size of the tree. The outstanding thing about this

tree and what called it to my attention was a patient who came into my

office complaining with a backache from picking up pecans on the 20th

day of August.

I wrote my friend, Mr. J. C. McDaniel, about this pecan, and when he

visited me during the Christmas holidays I gave him a sample. The only

thing that he could say bad about the pecan was that it was slightly on

the small side. I know personally that at least three or possibly four

bushels of good quality nuts were harvested from that tree, most of them

on the ground by the 20th of August.

In my section the Stuart pecan, which we use more or less as a

yard-stick, was ripe the latter part of October, and we thought that

possibly this tree, since it had undergone an unusually low temperature

the winter before of 20 below zero, might have possibilities.

But let's dispense with this pecan and say that we believe in the old

adage that one raindrop doesn't make a shower. It has a fair crop this

year, and they are just as green as my Stuarts now.

There is another tree that originated in West Tennessee which Mr.

McDaniel chose to call this nut "Rhodes heartnut." This tree is 7 years

old from a dormant bud on a 2-year-old black walnut seedling growing on

my back yard. It bore two clusters its second growing season, and since

that time it has borne annually, the crops increasing in proportion to

the size of the tree. This year's crop consisted of 88 clusters of nuts,

with an average nut count of 10.2 nuts per cluster, giving a total of

almost 900 nuts on this 7-year-old tree.

There is one more figure I'd like to give you. The count of clusters

compared to the number of terminals we had this spring is better than 90

per cent clusters. I have a few bud sticks here cut from green water

sprouts. That's the only kind I can find a sprout on. I brought them up

to Mr. McDaniel. If anybody can talk Mr. McDaniel out of a bud he wanted

to try, but I don't really know what plans he had for these bud sticks.

The 7 or 8 other varieties of heartnuts I have growing don't have any

that have clusters like the Rhodes.

Scab Disease in Eastern Kentucky on the Busseron Pecan

W. D. ARMSTRONG, _University of Kentucky, Princeton, Kentucky_

MR. ARMSTRONG: Mr. Chairman, ladies and gentlemen: It is nice to be here

at the Northern Nut Growers meeting. This is my second session. I attend

all the pecan and nut sessions in the country. I have attended

Georgia-Florida Pecan Growers Association and Oklahoma and Texas Pecan

Growers Association.

These plates that I have contain some of the Busseron pecans affected

with pecan scab. The disease has shown up in Southeastern Kentucky,

about a hundred miles southeast of Lexington, a hundred miles west of

the Virginia line, and about a hundred miles north of the Tennessee

line, on a straight line west of Roanoke, Virginia.

These trees were planted in bottom soil, rather well drained, and they

made a rapid growth. In the original planting there were two Green River

pecans, one Major, one Busseron and two walnuts, a Stabler and a Thomas.

About 1946 we noticed that all of the pecans on the Busseron were like

these that we have here--did not mature, completely covered with scab

fungus and dropped off the tree. The shells were so thin that you could

just crush the whole pecan, hull, shell and all with no meats in them.

The Major tree right beside it and the two Green River trees had none of

this trouble, and they have none of it as yet. And each year now that

this Busseron tree has borne there, practically all of the nuts have

been like this.

At the time we located this disease first in 1946, I sent samples to the

U.S.D.A. at Washington and also to the Southeastern Pecan Laboratory at

Albany, Georgia, and Dr. Cole, there identified it as pecan scab.

I reported the presence of the disease to Mr. Wilkinson and to Dr. Colby

and they were surprised to see the disease on Busseron in any location,

and particularly that far north.

In the south this disease frequently affects Schley, Delmas, Alley and

Van Deman and some others. Formerly the trees were sprayed with Bordeaux

Mixture. I think they are using Zerlate now. It's a problem to be

reckoned with. It occurs on the nuts and on the leaves, and it is

carried over winter on the stems and the one-year shoots.

Further News About Oak Wilt

E. A. CURL, _Illinois Natural History Survey, Urbana, Ill._

In 1951 a review of the oak wilt situation was given in a paper,

"Present Status of the Oak Wilt Disease", at the Forty-Second Annual

Meeting of the N.N.G.A. at the University of Illinois. The following

report is aimed at bringing up to date the present known distribution

of the oak wilt disease, recent developments in scientific research on

the disease, and possible control measures.

The oak wilt disease is caused by the fungus _Chalara quercina_ Henry

and is characterized by a very noticeable bronzing and wilting of leaves

that drop prematurely. Brown streaks are usually present in the outer

sapwood. These symptoms may be seen from June to September or until

normal autumn colors of the foliage develop.

More than 30 species of oak are known to be susceptible to the disease.

Other susceptible genera of the family Fagaceae are Chinese chestnut,

_Castanea mollissima_, golden chinquapin, _Castanopsis chrysophylla_,

tanbark oak, _Lithocarpus densifiora_, and _Nothofagus_ from South

America. The red and black oaks seem to be most susceptible and are

often killed within 6 weeks after infection.

Distribution

During the past few years the oak wilt disease has spread with such

rapidity and destructiveness among valuable forest and shade oaks in

parts of the eastern half of the United States that its seriousness is

now well recognized. At present oak wilt is known to be in the following

states: Wisconsin, Iowa, Minnesota, Illinois, Missouri, Indiana,

northern Arkansas, eastern Kansas, southeastern Nebraska, Ohio,

Pennsylvania, West Virginia, northwestern Virginia, western part of

North Carolina, eastern Tennessee, northeastern Kentucky, western

Maryland and southern Michigan. Aerial surveys for 1952 are not yet

complete, but there are indications of extensive new infections in

Pennsylvania, Ohio, and West Virginia while the other states show a

moderate increase in the number of infections.

The first case of oak wilt in Illinois was seen in Rockford in 1942.

Today 54 of the 102 counties in the state have oak wilt areas. The

disease is present in both the extreme northern part and the

southern-most tip of the state. Practically all wilt areas in the

southern half of Illinois consist of 5 trees or less that appear to have

died within the last 4 years, indicating a recent spread of the disease

southward. A similar condition exists in southern Missouri and northern

Arkansas.

Developments in Research

In 1942 a report from the Wisconsin Agricultural Experiment Station

revealed that the oak wilt disease was caused by a fungus, and research

programs were started early in Wisconsin and Iowa. Neighboring states

were quick to follow as surveys showed a wider distribution of the

disease. Now almost every state in which oak wilt occurs is taking part

in efforts to learn more about the disease and its causal agent so that

practical control measures may be applied before the spread of the

disease gets out of hand. The National Oak Wilt Research Committee at

Memphis, Tennessee, supports in part an intensive oak wilt research

program in coordination with several midwestern universities and with

the U.S.D.A., Bureau of Forest Pathology.

Until recently the causal fungus of oak wilt was known only in its

asexual or imperfect form living in the sap stream of infected trees.

The most important question to be answered now is how the fungus

spreads over long distances from diseased to healthy trees. Before this

could be accomplished, however, we had to know how the fungus escapes

from the inside to the outside of diseased trees where it can be exposed

to agents of dissemination.

In the late summer of 1951 clearly visible mycelial mats of the oak wilt

fungus were found in Illinois under the loose bark of wilt-killed trees.

These mats were usually located beneath cracks in the bark; thus, they

were exposed to the outside air and to visiting insects. Most

wilt-killed trees contain beneath the bark numerous insect larvae of

wood and bark boring beetles. Larvae were frequently found in direct

contact with mycelial mats of the fungus. Larvae of the two-lined

chestnut borer, _Agrilus bilineatus_, were most abundant, but larvae of

species of the families Scolytidae and Cerambycidae were also present in

large numbers.

In addition to the mycelial mat under the bark there was often present a

thick dark pad usually in the center of the mat. It is not known yet

what part this pad plays in the life history of the fungus but we do

know that it is produced by the same fungus which causes oak wilt.

We also found in Illinois that the oak wilt fungus often develops into

visible mats from chips of bark and wood that have been chopped from

wilt-killed trees and allowed to lie on the moist forest floor. This

should be remembered when considering sanitation as a partial means of

controlling the disease.

In 1951 the sexual or perfect form of the oak wilt fungus was produced

on laboratory media in Missouri by crossing different strains of the

fungus. The sexual form is recognized by the appearance of microscopic,

black, short-beaked fruiting structures or perithecia that are filled

with sticky ascospores. This sexual form is a species of

_Endoconidiophora_.

The sexual form of the fungus was first found in nature in Illinois in

the autumn of 1951. The perithecia are produced on the mycelial mats

beneath the loose and sometimes cracked bark of diseased oaks. Both the

ascospores of the sexual form and the endospores or conidia of the

asexual form will cause wilt if the spores are injected into oak trees.

From the foregoing information it is apparent that several methods by

which the disease might be spread over long distances are possible.

First, and what seems to be most probable, is transmission by insects.

Adult beetles, such as the two-lined chestnut borer, which emerge from

dead trees in the spring and feed on the leaves of healthy trees might

transmit the spores of the fungus. Other insects might feed on the

fungus mats that are exposed through cracks in the bark and carry both

the sticky ascospores and conidia to other trees. Additional agents that

must be considered are woodpeckers, squirrels and air currents.

Besides searching for the vector or vectors that spread the disease

other important studies are in progress. Among these is the

consideration of chemotherapy as a possible means of controlling oak

wilt. For our purpose, plant chemotherapy may be defined as the control

of disease by chemicals which are introduced into the plant. According

to Dr. Paul Hoffman of the Illinois Natural History Survey, a number of

chemicals have shown promise in curing small diseased oak trees when

treated in a very early stage of the disease. In one instance, trees

that were inoculated with the oak wilt fungus then treated with

chemicals 2 years ago are still alive. The most promising results were

obtained by injecting the chemicals into the soil where they are taken

up by the roots and by applying chemicals directly to the foliage in a

spray. Trunk injection showed least promise because of the limited

distribution of the chemicals through the tree.

The use of chemicals for curing wilt-infected trees is still in the

early experimental stage and is not yet recommended as a practical

control measure.

In 1949 Wisconsin workers demonstrated the local spread of oak wilt

through natural root grafts. They found that the poisoning of a single

healthy tree with sodium arsenite often killed as many as 15 other trees

nearby, indicating that their roots were connected.

Recently the results of experiments in Wisconsin explained in part what

causes the leaves of diseased trees to wilt. When a tree becomes

infected it is stimulated to produce tyloses or swellings in the vessels

of the wood. Therefore, the flow of water from the roots to the tree top

is restricted and the leaves wilt and die. It is also known that the

fungus itself produces a toxin which might be responsible for the actual

killing effect on the tree.

In Illinois experiments are being conducted with insects in relation to

the spread of oak wilt. Insects of various species are collected from

wilt-killed trees and allowed to run over or feed on laboratory cultures

of the oak wilt fungus. The insects are then caged on parts of healthy

trees to feed on the leaves. A single red oak treated in this way

contracted the disease and died. This shows that the disease can be

transmitted by an insect.

Controlling the Disease

The spread of oak wilt in local areas may be stopped by preventing the

underground movement of the disease from tree to tree through natural

root grafts. This can be done by (1) poisoning all healthy trees within

50 feet of diseased trees, (2) cutting a ditch 30 inches deep with a

small trenching machine between diseased and healthy trees to sever root

connections or (3) severing root connections with a tractor drawn plow

on which a knife blade is attached. Unfortunately the use of such heavy

equipment is not practical in rocky and hilly areas. Chemicals used for

killing trees are sodium arsenite and ammate. Ammate is safe to use but

does not kill trees as rapidly as the other poison. In some localities

2,4,5-T used as a trunk spray has given satisfactory results in killing

small trees.

If infected trees are left standing mycelial mats with their numerous

spores develop under the loosening bark. It is therefore advisable to

cut and burn all parts of diseased trees as soon as possible after

symptoms appear.

A combination trenching and eradication program was started in the

summer of 1950 in the Forest Preserve District of Cook County in

Illinois. According to Mr. Noel B. Wysong, Chief Forester, 2 newly

wilted trees were found in the Forest Preserve in 1948, 72 trees in

1949, 141 trees in 1950, and 96 trees in 1951. The count for 1952 is not

complete but a continued decrease in the number of new infections would

indicate good control.

There is no information on resistant species of oak. In very rare cases,

however, trees have been observed to recover after showing symptoms in

the early spring.

Future Outlook

Among the many things that we need to know yet about the oak wilt

disease and its causal fungus one is outstanding. How does the disease

jump from one infection center to healthy trees 200 yards, 2 miles or

even 100 miles away? Although spread through root grafts may be

controlled by severing root connections, the value of such a control

measure is limited as long as the agent or agents responsible for long

distance spread remain unknown. The discovery of other methods of spread

might result in the development of control measures that are cheaper and

less drastic than those known at present.

A great deal remains to be done and research is increasing in the

various states concerned. There is reason to believe that oak wilt can

be checked before it reaches devastating proportions comparable to

chestnut blight which wiped out our American chestnuts.

MR. SLATE: What is the origin of the fungus? Is it a native fungus, or

imported?

MR. CURL: Yes, it is a native fungus, as far as we know.

MR. SLATE: Any evidence that the fungus is mutating to make more

virulent strains?

MR. CURL: That's something that hasn't been found yet. There are several

strains of the fungus, what we call strains, because they will form the

sexual stage, and a strain alone will not. There is not too much known

about that yet, the strain business.

MR. GRAVATT: Just a word. We had a conference in Beltsville all day

Sunday about the recent developments on the oak wilt. There has been

very extensive spread in Pennsylvania, Ohio, West Virginia and Maryland

this year. We are very much alarmed about the situation. The Chinese

chestnut is very severely affected. We have learned that in Missouri.

One year there were three Chinese chestnuts killed by the fungus, the

next year 60. The oak wilt is a serious threat to the chestnut orchards.

Life History and Control of the Pecan Spittle Bug

STEWART CHANDLER, _Associate Entomologist, Ill. Nat. History Survey,

Urbana, Ill., Consulting Entomologist, Southern Illinois University_

Since it was a year ago that this subject of spittle bug was first

brought to the attention of the Northern Nut Growers Association, it

might be well to review briefly the high lights of that report. I told

you at the annual meeting at Urbana, something of the life history.

There are two broods, one appearing in June and one in July. The adult

is a small sucking bug about an eighth to a quarter inch long. The

species at that time was uncertain but now has been determined by

specialists in that group as _Cercoptera achatina_ Germ. This insect, I

reported, is not the same as the one occurring on meadow and other

field crops, not only the species but the genus being different. The

distribution was found to be in every area where pecans are grown. As to

its importance I pointed out that in Illinois it had become very serious

in the past three or four years, apparently causing a marked reduction

in crop. Control measures were directed against the nymphal stage, which

is protected by the spittle which the insect emits continuously while

feeding. Three insecticides were tested at Anna, Illinois, Lindane,

parathion, and tetra ethyl pyro phosphate, known as TEPP. Lindane proved

to be approximately 95% efficient, parathion roughly 60% and TEPP about

10%.

In 1952 the work was resumed in the orchard of Conrad Casper near Anna,

Illinois and was begun at the Richard Best place at Eldred, 175 miles

northwest.

In 1952 five phases of the work with pecan spittle bug were undertaken

as follows:

1. A study of the importance of the pecan spittle bug.

2. The hibernation of the insect.

3. Life history and occurrence of the various stages and broods of

the insect in relation to nut development of the pecan.

4. Control measures.

5. Varietal susceptibility to the insect.

1. Importance of the insect

_Hibernation Studies_

To learn to what extent if any the insect reduces the crop of pecans,

terminal shoots from trees sprayed the previous season with three

different materials were compared with the unsprayed check. These are

shown in Table 1.

Table 1. Pecan spittle bug effect of 1951 sprays on terminal shoots in

spring of 1952

===================================================

Dead shoots

Treatment per hundred

Check 87

TEPP 62

Parathion 17

Lindane 4

===================================================

Since these terminals shoots later develop most of the nuts it would

appear that the pecan spittle bug is responsible for much of the loss of

crop under these heavy infestations.

It was planned to follow this up with later examination of nuts, and

this was done with the assistance of Mr. J. C. McDaniel, but

unfortunately it was found that this was the off year and the crop was

very small, so we could not definitely settle that point. This will be a

job for the future.

2. Hibernation studies.

In August of 1951, I introduced adult bugs into a cage placed over a

branch of an unsprayed pecan tree for the purpose of determining whether

there was possibly a third brood. Finding none the branch was removed

and examined to study the hibernating eggs and the egg slits in which

they were layed. The slits were not over a quarter inch long and

frequently in pairs. Eggs were deep enough that they were rarely seen

without opening the slits. Many slits were found containing egg shells,

presumably from the previous brood, but possibly from a season earlier

as the slits are corked over.

Following this study branches were cut from the sprayed and unsprayed

blocks and gone over very carefully to find the numbers and location of

the egg splits and the numbers containing live eggs and egg shells. Each

split would contain as many as 5 or 6 eggs. Table 2 show their numbers

and locations, and Table 3 the effect of sprays on numbers of live eggs.

Table 2. Pecan Spittle Bug Location of egg slits in branches

=================================================================

Diameter of branches, inches

1/8 to 1/4 3/4 3/8 1/2 1/2 to 1 inch

-----------------------------------------------------------------

Live eggs 2 9 3 1 0

Egg shells 5 42 94 23 0

-----------------------------------------------------------------

Table 3. Pecan Spittle Bug Effect of 1951 sprays on number of eggs

Examinations made March 4, 1952

=======================================================

Inches wood Number of Slits with

Treatment examined live eggs egg shells

-------------------------------------------------------

Check 508 10 63

TEPP 795 5 25

Lindane 478 0 13

-------------------------------------------------------

3. Life history and correlation of stages of insect and nut development.

It was soon found that the pecan spittle bug was putting in its

appearance earlier according to the calendar than in 1951 so an effort

was made during the season to correlate insect life history and nut

development during the season. Table 4 give some of the principal points

in both.

Table 4. Pecan Spittle Bug and Nut Development Anna, Illinois, 1952

--------------------------------------------------------------

Insect Date Tree

--------------------------------------------------------------

Egg stage Apr. 24 Catkins 1/2 to 3/4 inch

First nymphs May 5 Catkins 1 to 1-1/2 inch

Many nymphs and spittle May 12 Catkins 2 to 3 inches

Fruit buds

Peak hatch May 20 Female flowers

Spittle drying June 2 Nuts developing

1st. 2nd brood June 27

Hatch mostly over July 7

Spittle drying July 26

--------------------------------------------------------------

Another phase of life history which is of practical importance is the

increase of second brood over first. Records were made both at Anna and

at Eldred in unsprayed blocks at approximately the peaks of occurrence

of nymphs and spittle, and are tabulated in Table 5.

Table 5. Pecan Spittle Bug Infestation, first and second broods, 1952

Number of spittle masses per 100 terminals

==========================================================

First brood, June Second brood, July

----------------------------------------------------------

Anna 41 62

Eldred 23 50

----------------------------------------------------------

This table shows an increase of approximately 50% at Anna and 100% at

Eldred. It is thought that a 3 inch flash flood which occurred at Anna

might have reduced the first brood infestation somewhat after the counts

were made and been responsible for no greater increase and possibly that

the heat and drought in both places might have resulted in a reduction.

Be that as it may the total infestation was not as severe in 1952 as in

1951.

4. Control.

_First Brood Sprays_

It was originally planned to spray in both places but at Anna the owner

sprayed all but the 1951 check block with parathion early and the

infestation was reduced to the point where later hatch did not build up

to a sufficient point that good results could be observed so no spraying

was done at Anna till the second brood. At Eldred two materials only

were available, Lindane and Dieldrin.

At Eldred we had two difficulties in spraying. One was the type of

machine with which I was not familiar and the other the inaccessibility

of some of the trees. The machine is probably more fitted for field crop

work than for large trees. It is called a Mechanical Aresol Generator,

manufactured by the Hessian Microsol Corporation of Darien, Conn. The

engine is a Wisconsin Air cooled motor made in Milwaukee, Wisconsin. The

machine was mounted on a platform and transported in the orchard on a

truck. Two fifty gallon barrels constitute the tank. Due to the nature

of the machine and to lack of agitation only liquid materials can be

used in it. It uses a much smaller amount of material than I had been

accustomed to, and my first job was to learn to what extent the

materials must be concentrated to compensate for the small output and

how to get a comparison with the amounts used in regular orchard

sprayer. In concentrate tests on fruit trees we arrive at this by

judging the number of gallons which a tree would normally receive with a

standard sprayer. There was little background to go on with nut trees

and the problem was further complicated by the arrangement of trees

which were not planted but grafted in their original positions in the

woods. A clump of trees which could not be approached individually might

have to receive not much more material than one tree which could be hit

from both sides. Sizes of trees also varied. It was decided to use only

25 gallon lots of material and even this small amount sprayed from 55

to 65 trees of varying sizes. It was soon seen that the tops of the

moderate and large sized trees were not covered very well. For the first

brood sprays at Eldred about six times as much material per 100 gallons

was used as had been successful at Anna the previous season. The results

are shown in Table 6.

Table 6. Spittle Bug Control, Eldred, 1952 First brood, sprayed May 23,

examined June 9

=========================================================

Treatment Amount in Spittle masses

100 gallons 800 terminals

---------------------------------------------------------

Dieldrin 1 gal. of 18-1/2% 18

Lindane 1 gal. of 20% 27

Check ------ 189

---------------------------------------------------------

It will be seen that the reduction over the unsprayed blocks was about

90% with Dieldrin and 85% with Lindane.

For second brood sprays at Eldred materials were increased to about 8

times normal in hopes of getting better results. In this test 10 trees

were selected in each block that could be reached moderately well and

sprayed separately before the entire block was sprayed. Records were

made the day before spraying, 3 days after spraying, and 10 days after

spraying. Four materials were available, making five blocks with an

unsprayed check. The results of these sprayings are given in Table 7.

Table 7. Spittle Bug Control, Eldred, 1952 Second brood, sprayed July 18

============================================================

Treatment Amounts in In 200 terminals

100 gallons July 17 July 21 July 28

------------------------------------------------------------

Lindane 6 qts. of 20% 123 24 2

BHC 10 qts. of 11.7% 98 11 0

Dieldrin 6 qts. of 18-1/2% 130 19 9

Toxaphene 8 qts. of 58% 107 16 3

Check ------ 99 98 47

------------------------------------------------------------

Due to the natural reduction in the check by July 28 most attention

probably should be given to the July 21 examination. This table shows

approximately 92% reduction from Lindane, 87% with BHC, 85% from

Dieldrin, and 85% from Toxaphene on July 21.

At Anna trees are all very big, from 50 to 75 feet high. They are

planted in rows. A regular orchard sprayer was used with 600 pounds

pressure using one gun and sprayed from the top of the rig.

Approximately 25 gallons was used per tree. As will be noted the dosage

was much smaller than at Eldred, and for ordinary use these are probably

the proper dosages. Table 8 gives the results of these tests.

Table 8. Pecan Spittle Bug Control, Anna, 1952

==================================================================

Treatment Amounts in In 200 terminals

100 gallons July 10 July 14 July 22

------------------------------------------------------------------

Lindane 1 lb. of 25% 214 1 1

BHC 2-1/2 lbs. of 10% 244 5 9

Dieldrin 1 and 1/3 pints of 18-1/2% 148 3 5

Toxaphene 1 qt. of 31% 146 22 21

Check 61 47 20

-------------------------------------------------------------------

The reduction in the check block July 14 may be due to proximity to the

sprayed block which was not true in Eldred. This check was small. Table

8 shows on July 14 an approximate reduction of Lindane 99%, BHC 98%,

Dieldrin 98%, and Toxaphene 85%.

From these tests in both places it appears that we have a choice of

three very good materials, Lindane, Benzene hexachloride called BHC and

Dieldrin, and for that reason we can ignore the less efficient material,

toxaphene.

At Eldred, since first brood sprays were applied in a sizeable area

records of infestation were made shortly before time to spray for the

second brood to determine whether the first brood spraying would

eliminate the need for second brood spraying. However, the infestation

was found to be practically as great in this area as the unsprayed part

of the woods. It appears that the control was not good enough to allow

this. In part this was due to failure to reach the tops of the trees.

Records were made in the lower parts.

5. Varietal susceptibility.

At Anna where there was a limited number of trees, the orchards were

plotted on paper and location of each tree with variety indicated

records were made of each tree separately, in hopes that some varietal

susceptibility would be shown. There is nothing very clear in this

respect except that of the varieties in the Casper orchard, Butterick,

Busseron, Indiana, Posey, Stewart, Osburn, Major, Green River, the

Indiana and Posey may be a little more heavily infested than the others.

At Eldred for the second brood infestation, the variety of each of the

10 record trees was reported, but there were so many varieties and they

did not occur often enough in the five plots to make variety infestation

data reliable. However, the rather high average on the Indiana variety

did seem to corroborate the findings at Anna.

There was some foliage burn in two of the record trees in the Dieldrin

plot at Eldred, both being the variety Rockville. Another tree in

another part of the plot was also found to be burned and also found to

be the same variety, so it appears that this may be particularly

susceptible to spraying especially in this concentrated form such as we

used. There were no Rockville trees in any of the other plots, so we

have no way of knowing whether the Lindane, BHC or Toxaphene would have

done the same or not.

PRESIDENT MacDANIELS: The next paper, the last paper of the afternoon,

is Control of Insects Injuring Nut Trees, by Howard Baker, U.S.D.A.

Bureau of Entomology and Plant Quarantine, Beltsville, Md.

MR. BAKER: Mr. Chairman, members of the Northern Nut Growers

Association: It is a great deal of pleasure to be back here speaking

before a group of nut growers. Back some years ago my first assignment

to a station of which I had charge was an investigation to count insects

in Louisiana and Eastern Texas, so it is a pleasure to be back before a

group of nut growers.

Insect Enemies of Northern Tree Nuts

HOWARD BAKER, _U.S.D.A., Agr. Res. Admin., Bureau of Entomology and

Plant Quarantine_

The small number of requests for information on insect pests of northern

tree nuts received in the Bureau of Entomology and Plant Quarantine is a

strong indication that such pests are of little concern to northern nut

growers. This is fortunate, because intensive, all-season spray

programs, such as are necessary to produce most other crops without

serious losses due to insect injury, are laborious and expensive and not

always as effective as desired. However, as your acreage is increased

and as your trees become older and larger, insect problems are likely to

increase in number and intensity and require more of your thought and

attention.

A somewhat similar situation prevailed in the pecan industry at one time

in the South. I well remember the statement of one of the larger pecan

growers in Louisiana to the effect that all the pleasure of growing

pecans would be gone the day he had to start spraying to control insects

and diseases. Only a short time later it became necessary for him to

initiate a regular spray program. He still took great pride in growing

pecans, however. It is well, therefore, for you to watch your trees

closely for insect damage and keep informed concerning the habits and

control of the species that show up in your plantings or in those of

your neighbors.

Because of the scattered nature of the northern nut industry, the small

size of most plantings, and the more pressing demands for information on

the control of pests of more intensively planted crops, it has not been

possible for the Bureau of Entomology and Plant Quarantine to give

attention to many of the pests of northern nuts. A great deal of work

has been done on the pests of pecans in the South, and some work on

those that attack filberts and chestnuts. In addition, some of the pests

with which you are concerned, or others similar to them, are receiving

attention in connection with studies of pests of tree fruits. The

results of these studies will give you up-to-date information applicable

to your particular problems.

The timely use of insecticides is the most effective means of combating

most injurious insects, but if spraying is not possible, other methods

can often be used to prevent or reduce damage. A great many new

insecticides have become available during the last six or seven years.

Work with them has resulted in the development of treatments effective

against a number of pests for which there was formerly no known means of

control and markedly more effective treatments for the control of

others. It is my purpose to bring to you as much of this new information

as is applicable to your problems.

Leaf-feeding Caterpillars

The fall webworm[3] and the walnut caterpillar[4] are the leaf-feeding

caterpillars most commonly reported as attacking northern tree nuts.

Fall webworms[5] are the insects usually responsible for unsightly webs

on or near the end of the branches of the trees during the summer and

fall. They enlarge the webs as they need more leaves. When nearly full

grown they scatter to complete their feeding. The full-grown

caterpillars are a little more than an inch in length and are covered

with long black and white hairs. They spend the winter in cocoons in

trash on the ground or just below the surface of the soil. There are two

broods a year in many areas, the second usually being the more numerous.

Control can be obtained by applying a spray containing 3 pounds of lead

arsenate with an equal quantity of hydrated lime (to prevent possible

injury to the foliage), 2 pounds of 50-percent DDT wettable powder, or 2

pounds of 15-percent parathion wettable powder per 100 gallons of water.

Apply the spray when the caterpillars are still small. Follow the

precautions furnished with each package. Parathion is a particularly

dangerous material to use. If you are not equipped to spray or have only

a few trees, you can control this insect by removing the webs from the

trees with a long-handled pruner or a long bamboo pole with a hook at

the end.

The walnut caterpillar feeds in groups, or colonies, and commonly eats

all the leaves on small trees or on certain limbs on large trees. The

winter is spent in cocoons in the ground. The moths appear late in the

spring or early in the summer and lay masses of eggs on the underside of

the leaves. From time to time as they grow, the stout, black

caterpillars go down to a large limb or to the trunk of the tree to

molt, or shed their skins. After molting they return toward the ends of

the branches and resume their feeding.

This insect can be controlled with the same spray treatments that are

recommended for the fall webworm, and also by crushing or burning the

caterpillars when they are clustered on the lower limbs or tree trunks.

Pecan Phylloxera[6]

Swellings called galls sometimes appear on leaves, leafstalks, succulent

shoots, or nuts of the current season's growth of hickory and pecan.

These galls are caused by small insects known as phylloxera, which are

closely related to aphids, or plant lice. Several species are involved,

but only one, known as the pecan phylloxera, causes serious damage. It

causes twigs to become malformed, weakened and finally to die, and

destroys the crop on the infested terminals. The insect passes the

winter in the egg stage in protected places on the trees. The young

appear in the spring about the time the buds begin to unfold.

The phylloxera can be controlled by spraying the trees thoroughly with a

mixture containing 3/4 pint of nicotine sulfate plus 2-1/2 gallons of

lime-sulfur or 2 quarts of lubricating-oil emulsion to 100 gallons of

water during the delayed dormant period or by the time buds show about

an inch of green. Sprays containing 3 pounds of BHC (10-percent gamma)

or 1-1/4 pounds of 25-percent lindane wettable powder per 100 gallons

are also effective, and their use is increasing. Other materials have

given good control when applied about the time the buds begin to swell.

They are 36-percent dinitro-o-sec-butylphenol liquid, 3 quarts per 100

gallons, and a mixture of 40-percent dinitro-o-cyclohexylphenol powder,

2 pounds, and lubricating-oil emulsion, 5 quarts, per 100 gallons of

spray. Do not use the dinitro materials after the buds begin to open.

Twig Girdler

A stout, brown beetle about 1/2 inch in length, known as the twig

girdler,[7] often cuts off the twigs of hickory, pecan, and many other

trees in the late summer and early fall. The larvae spend the winter in

the cut twigs, which are gradually broken off and fall to the ground.

Injury can be reduced by collecting and destroying the fallen twigs

before the larvae complete development the following spring. Recent work

on pecans in Florida indicates that most injury can be prevented by

applying a spray containing 4 pounds of 50-percent DDT or 3 pounds of

15-percent parathion wettable powder per 100 gallons of water. Three

applications appear to be necessary, the first when the injured branches

are first noticed, usually sometime in August, and the second and third

two and four weeks later. When handling parathion be sure to follow the

precautions on the package.

Weevils and Curculios

Weevils and curculios are small, hard-shelled, grayish to brown beetles

about 1/4 to 1/2 inch long, with stiff, slender snouts or beaks. They

feed and lay eggs in the nuts and/or shoots of many kinds of nuts,

including hickory, walnut, pecan, chestnut, hazelnut or filbert, and

butternut. There are a number of species, but most of them attack only

one kind of nut. The species usually called weevils most often lay eggs

and injure the nuts from the time the meat begins to form until it is

mature, whereas the group known as curculios generally emerge and cause

most serious damage during the early part of the growing season, when

the new shoots are developing and the crop starts to set and grow.

The chestnut weevils are probably the weevils best known to most of you.

E. R. VanLeeuwen, of the Bureau of Entomology and Plant Quarantine, has

added much to our knowledge of these weevils in recent years. Two

species, the small chestnut weevil[8] and the large chestnut weevil,[9]

are commonly present together and cause similar injury. The small

chestnut weevil appears as an adult over a period of about 6 weeks

beginning near the first of May in the vicinity of Beltsville, Md., but

it does not lay eggs until about the middle of August. The larger

species does not emerge until about the middle of August and begins to

lay eggs soon thereafter. Eggs are laid in the developing nuts, and

injury is caused by the feeding of the larvae therein. Most of the small

weevils require two years to complete development, and most of the

larger weevils but one year.

Some control of these weevils can be obtained by collecting and

destroying the infested nuts before the larvae leave them to enter the

soil. Better control can be obtained by spraying the trees with DDT.

Apply a spray containing 4 pounds of 50-percent DDT wettable powder per

100 gallons of water (3 level tablespoonfuls per gallon) 30 days before

the first mature nuts are expected to drop, and make two additional

applications at intervals of 7 days. If you are not equipped to spray,

you may obtain some control by treating the soil under the trees with

ethylene dibromide at a depth of 5 inches. Make injections at intervals

of 1 foot in each direction and also in the center of each square formed

by these injection holes. Place 1 milliliter of 40-percent ethylene

dibromide or an equivalent quantity of another dilution in each hole.

Make the application in the fall immediately after the nuts are

harvested and close the injection holes by pressing with the foot. The

soil should preferably be loose to a depth of 5 inches.

The pecan weevil,[10] also known as the hickory nut weevil, often causes

heavy losses of pecans and most species of hickory. Two or three years

are required for the insect to complete its life cycle, but some

specimens reach maturity every year. Adults emerge from the ground from

the middle of July until early in September, according to locality and

seasonal conditions. Injury is of two types--(1) that resulting from

attack before the shell-hardening period in July and August, causing the

young nuts to drop, and (2) that resulting from attack after kernel

formation, the kernel being destroyed by the developing larvae, or

grubs. Egg deposition in the nuts usually begins late in August.

To control this weevil spray the trees twice with 6 pounds of 50-percent

DDT or 40-percent toxaphene wettable powder per 100 gallons of water.

Make the first application when at least six weevils can be jarred onto

a sheet on the ground beneath any tree known to have been infested in

previous seasons, and make the second 10 to 14 days later. The first

application will be needed sometime between the last week in July and

the first week in September. If the soil is hard and dry, it will delay

emergence of the weevils. If you are not equipped to spray, you can

reduce weevil injury about 50 percent by jarring the limbs of the trees

lightly and gathering the weevils on a sheet during the period of

emergence. The dislodged weevils will remain quiet on the sheet long

enough to be picked up and destroyed. Begin jarring about the last week

in July and confine it to two or three trees until the first weevils

appear. Then jar all trees at weekly intervals until about the middle of

September, when egg laying will have been largely completed.

The butternut curculio[11] attacks native butternuts and introduced nuts

of a similar type. It passes the winter as an adult in trash or other

shelter it can find in the vicinity of nut trees. It is a small,

hard-shelled, rough-backed snout beetle. Late in the spring it makes its

way to the trees, and lays eggs in the young shoots. On hatching, the

young larva penetrates into the young shoot or leaf stem or nut and

feeds there, causing the leaf or nut to dry up and fall off. Upon

completing development in the fallen leaf or nut, the mature larva

enters the soil. After a month or so in the ground the adult emerges,

feeds on the foliage for a while, and then enters hibernation. There is

but one generation a year.

The black walnut curculio[12] is similar to the butternut curculio in

seasonal history, but it attacks principally the fruit of the black

walnut and butternut, apparently preferring the former.

The hickory nut curculio[13] is much like the preceding two species, but

it attacks chiefly partly grown hickory nuts, causing a heavy dropping

in midsummer.

The hickory shoot curculio[14] attacks chiefly the shoots of various

kinds of hickory. The damage is seldom of much importance except to

newly transplanted trees. On pecan it attacks the unfolding buds and

shoots. Pecans most commonly attacked are those that are uncultivated or

are adjacent to woodlands containing native pecan and hickory trees.

For many years these curculios have been controlled by spraying the

trees soon after growth starts with lead arsenate, 2 pounds per 100

gallons, plus an equal amount of hydrated lime. One or two additional

applications may be needed as new growth appears or as the nuts increase

in size. Recent experimental work indicates that BHC or lindane may be

more effective for controlling these insects. A spray containing 3 or 4

pounds of technical BHC (10-percent gamma) or 1-1/2 to 2 pounds of

25-percent lindane wettable powder per 100 gallons, applied when the

buds show from 1/4 to 1 inch of green growth or when jarrings show

adults are present, has given fairly good control.

Walnut Husk Maggot

The walnut husk maggot[15] attacks black and English walnuts,

butternuts, and a few other nuts. The feeding of the larva, or maggot,

in the husks impairs the quality of the kernels, discolors the shell,

and often causes the shells to adhere to the nuts. It causes the most

damage to English walnuts. This insect hibernates in the pupal stage in

the ground. In midsummer it transforms to the adult fly stage, leaves

the soil, and flies to the nut trees. After 1 to 3 weeks the flies lay

eggs in the husks of the developing nuts. The eggs hatch in a week or 10

days, and the young maggots burrow within and throughout the husks of

the nuts; they mature in the fall.

The walnut husk maggot can be controlled by spraying the trees with lead

arsenate or cryolite the latter part of July and again 3 to 4 weeks

later. Use 2 or 3 pounds of lead arsenate plus an equal quantity of

hydrated lime or 3 pounds of cryolite per 100 gallons of water.

Filbert Moth

The filbert moth,[16] a serious pest in some filbert orchards in Oregon,

also causes some injury to chestnuts. Adult moths begin emerging toward

the end of June and lay their eggs singly on the leaves beginning early

in July. The newly hatched larvae tunnel through the husk and feed

between the husk and the chestnut shell before entering the nut. This

feeding produces a gummy substance, which causes the husk to adhere to

the nut. The larvae may tunnel into the center of the kernel or excavate

an irregular cavity in the side. They reach maturity about the time nuts

are ripe, and then leave the nuts and construct cocoons in the soil in

which to pass the winter.

Control can be obtained by spraying the tree with lead arsenate or DDT

early in July. Use 3 pounds of lead arsenate or 2 pounds of 50-percent

DDT wettable powder in 100 gallons of water.

Mites

Two general types of mites sometimes damage nut trees, eriophyid mites

and spider mites. The most important eriophyid mites are the wormlike

gall mites and bud mites, most of which overwinter in the buds and cause

deformities of the buds and leaves and otherwise limit their

development. The spider mites may overwinter in the egg stage on the

twigs or as adults in protected places on or beneath the trees. These

mites feed primarily on the foliage.

The filbert bud mite[17] is occasionally of economic importance as a

pest of filberts in Oregon and has been of some concern recently in New

York. It attacks the leaf and flower buds and catkins. Infested catkins

become distorted, rigid, and brittle, and yield no pollen. In Oregon

this pest has been controlled with 3 gallons of a dormant oil emulsion

or 6-1/2 to 8 gallons of liquid lime-sulfur in water to make 100 gallons

of spray just as the buds are opening. Related species of similar habits

that attack walnuts have been controlled with 9 or 10 gallons of liquid

lime-sulfur in water to make 100 gallons of spray applied at the time

the buds break or soon thereafter.

The feeding of the spider mites on the foliage of infested trees causes

it first to have a bronzed or scorched appearance, and later to dry up

and fall. These mites frequently become abundant following the use of

some of the new organic insecticides, such as DDT and BHC, which destroy

their natural enemies and perhaps have other effects on the trees

favorable to mite activity. The European red mite, which overwinters

on the trees in the egg stage, can be controlled by application of

3-percent oil-emulsion spray in the late-dormant period. The two-spotted

spider mite and related species, as well as the European red mite if it

is not controlled with the dormant spray, can be controlled with a spray

containing 1 pound of a 15-percent parathion or 1-1/2 pounds of a

15-percent Aramite wettable powder per 100 gallons. Apply the spray

before many leaves show the typical bronzing or leaf scorching. If the

infestation is heavy, a second application may be necessary in about 8

or 10 days. Be sure to follow the precautions on the container,

especially if you use parathion.

PRESIDENT MacDANIELS: We greatly appreciate your care in getting this

thing together, and we know it is going to be a great help to us when we

get it printed as a matter of reference.

MR. O'ROURKE: I'd like to ask Dr. Baker if insects are getting stronger

or if the chemicals are getting weaker. I refer to the rates of

application. Formerly we were told that one-half pound of parathion for

one hundred gallons and one pound of DDT would control almost all

insects. I note the rates are going up.

MR. BAKER: That's true, particularly with parathion. The first year that

we tested parathion on any scale we thought a quarter to a half a pound

would control mites for 30 days or more and would control curculio for

20 or 30 days, but the next year we used it we found that was a little

optimistic. It seems that each year since we have had to use more of it

or use it more often, or with mites, particularly, there are a number of

instances where it just doesn't control them at all.

Two years ago that came to notice in the Wenatchee area of Washington on

apples. Mites in a certain orchard just couldn't be controlled with

parathion. A year ago the area in the Pacific Northwest where that was

true was extended and included several orchards of the Yakima Valley.

This year it also includes orchards in the East, in New York. We have

seen an orchard where two pounds of parathion and a hundred gallons of

water just didn't have much effect on the mites, and we have had to use

other materials. We hear of instances of codling moth on apples where

DDT doesn't seem to be as good as it was in the beginning. I have talked

with some of the people working on the problem, and they find that there

is quite a difference between different brands of some of these

insecticides. Possibly that is the answer.

MR. MACHOVINA: After spraying for shuck maggot with DDT do you encourage

the presence of mites?

MR. BAKER: It's very possible that you might. That has happened where

DDT has been used. With some of our work with chestnut weevils, mites

seem to be a little more abundant where we used DDT. We have had reports

of this happening in California where they used DDT on walnuts. So it is

a possibility, and that's why I brought into the paper a little

information on the control of mites.

Session closed at 4:15 o'clock, p.m.

FOOTNOTES:

[Footnote 3: _Hyphantria cunea_ (Drury).]

[Footnote 4: _Datana integerrima_ G. & R.]

[Footnote 5: _Clastoptera achatina_ Germ.]

[Footnote 6: _Phylloxera devastatrix_ Perg.]

[Footnote 7: _Oncideres cingulata_ (Say).]

[Footnote 8: _Curculio auriger_ Casey.]

[Footnote 9: _C. proboscideus_ F.]

[Footnote 10: _Curculio caryae_ (Horn).]

[Footnote 11: _Conotrachelus juglandis_ Lee.]

[Footnote 12: _Conotrachelus retentus_ Say.]

[Footnote 13: _Conotrachelus affinis_ Boh.]

[Footnote 14: _Conotrachelus aratus_ Germ.]

[Footnote 15: _Rhagoletis suavis_ Loew.]

[Footnote 16: _Melissopus latiferreanus_ (Wlsm.)]

[Footnote 17: _Phytoptus avellanae_ Nal.]

TUESDAY EVENING BANQUET SESSION

We will now have the report of the Resolutions Committee.

MR. DAVIDSON: "To Royal Oakes, Chairman of the Program Committee, and to

J. Ford Wilkinson, the City of Rockport and its hospitable people, the

Northern Nut Growers Association extends its grateful greetings to you

and to your loyal helpers, mentioning only a few; that is, Mrs. Negus,

Mr. and Mrs. Sly, Mr. Richard Best, a group of people who say little and

who do much, our very hearty thanks to you and to your helpers. We have

had a splendid meeting, good attendance, good fellowship and tomorrow a

good field trip.

"RESOLUTION: The sincere and grateful appreciation of this Association

is hereby tendered to J. C. McDaniel, who has so faithfully and

fruitfully served it as Secretary for five years. Your creation of new

avenues of service, such as _The Nutshell_ is sufficient evidence of

your resourcefulness in a difficult and most important office.

"RESOLUTION: Be it resolved, that this Association instruct its Secretary

to communicate the following action to the responsible agencies of

Federal and State authorities in all areas where the oak wilt disease is

present or threatens:

"'The oak wilt disease threatens severe damage to our eastern and

southern oaks and Chinese chestnut trees. Recently reported spread of

the disease in Ohio, West Virginia, Maryland and Pennsylvania indicates

a very serious and critical situation. All state and federal authorities

are urged to take prompt and appropriate action before it is too late.'"

All NNGA members are asked to write to their state and federal senators

and representatives urging immediate preventive measures against the

spread and for the eradication of the oak wilt disease. Please write

those letters. They are important.

"To Dr. Deming, greetings and congratulations from your Association on

the occasion of your 90th birthday, September 1, 1952. May your years

continue to be golden and happy. May our organization deserve in the

future the gifts of inspiration and accomplishment that you have had so

large a part in giving it in the past."

"To Dr. J. Russell Smith: The Northern Nut Growers assembled at Rockport

send greetings and best wishes to you. We miss you this year and hope to

see you at Rochester, New York, next year."

"To Mildred Jones Langdoc. Mildred: We have missed you at our meeting.

Your absence is noted by all who know you. May the illness in your home

be short. May we see you and your family in Rochester in 1953."

"RESOLUTION: On behalf of the members of the Northern Nut Growers

Association the Secretary is asked to send our affectionate greetings to

two well-loved, absent members, Mrs. C. A. Reed and Mrs. G. A.

Zimmerman: 'Best wishes to you both for speedy recovery of good health

and with our hope to see you next year.'"

PRESIDENT MacDANIELS: Is it your pleasure to adopt these resolutions all

at once, or do you wish to separate them? I take it that you wish to

adopt them, all at the same time, and to that end a motion to accept the

report of the Resolutions Committee and to adopt the resolutions and to

send the greetings would be appropriate.

The report of the resolutions committee was accepted unanimously.

MR. MCDANIEL: Before this meeting convened we planned a bud wood

exchange at the convention. Mr. Gerardi and I brought some buds, and Mr.

Richard brought a few of the Rhodes heartnut. We have persimmons, some

buds of the new Crandall apple, and a few sticks of Chinese and hybrid

chestnuts. They are for anyone who would like to experiment with them.

PRESIDENT MacDANIELS: Next year at Rochester we are going to have

opportunity for putting on a considerable exhibit of nuts, and I think

that it would be much to the advantage of the Association, if we could

have an outstanding exhibit there where there is a good chance to have a

large number of people see the exhibits and become interested. To that

end I think that all of us who have nut trees bearing this fall, should

save some samples with extra care; that is, clean them up, make them

look attractive and have them on hand ready for the exhibit next fall.

A good sample for exhibit should be about 10 or a dozen for black

walnuts and the Persian walnuts and perhaps 20 to 25 for the hickories

and the smaller nuts, the hazel, particularly. I think that we have a

good chance next year to forward the cause of the Association, and

certainly having these exhibits will be much to our advantage.

At this time, towards the end of our session, it is our usual custom to

elect our next year's officers. Before going on with that election, I

would just like to say that I personally, as president of the

Association during this year, wish to thank all of the other officers

who have worked with me. It has been a pleasure to work with them and

with the committee chairmen, and I think the meeting here at Rockport

and the work during the year attest to their effective service.

The Nominations Committee report. For president next year, Mr. R. B.

Best; for vice-president, George Salzer of Rochester, New York; for

Treasurer, Carl Prell of South Bend, Indiana, who continues in the

office; and for Secretary Mr. Spencer Chase of Norris, Tennessee.

The slate presented was elected unanimously.

A nominating committee consisting of Max Hardy, Gilbert Becker, George

Slate, Dr. William Rohrbacker, and Ford Wilkinson was unanimously

elected for 1953.

PRESIDENT MacDANIELS: I will now call upon our newly elected president

to come forward. It is usual at these meetings for the retiring

president to present the gavel to the incoming president, and here it

is. This gavel is made of pecan wood presented to the Association by Mr.

T. P. Littlepage, who was born in this locality. I hope you will have as

much fun and pleasure as president of the Association as I have had.

It's all yours.

MR. WILKINSON: That gavel was made from the wood of a pecan tree. Mr. T.

P. Littlepage planted the nut when he was 14 years old on a piece of

land that he inherited as a boy. I cut the wood and sent it to him in

Washington to have the gavel made of it.

Chestnut Breeding

Report for 1951-1952

ARTHUR H. GRAVES[18] and HANS NIENSTAEDT, _Connecticut Agricultural

Experiment Station, New Haven, Conn._

Weather Conditions

Two serious enemies of the chestnut, if we disregard parasitic

organisms, are drought and extreme cold. The winter of 1950-51 was

unusually mild--scarcely cold enough to freeze the ground. The

precipitation was plentiful during the winter months so that the water

table was sufficient to tide over a slightly dry June and a much more

serious drought in September and early October. But the latter dry

period came when the nuts were matured, or nearly so.

The winter of 1951-52 was again mild except for a short cold spell at

the end of January, with plentiful precipitation up to the first week of

June, and then a long drought with the driest July since 1944. However,

the heavy rainfall of August, 8.69 inches,[19] made amends for this,

and with the normal rainfall of 3.48 inches of September, prepared the

trees to endure the long drought of October and early November. This

serious drought,[20] which resulted in disastrous forest fires filling

the air with smoke over much of the New England States, came late,

however, after the nuts were nearly matured, some of the early kinds

being ripe as early as the first week in September.

The excessive heat of July, in which month occurred the greatest number

of days on record with a maximum temperature of 90 degrees or above, was

probably the chief cause of somewhat smaller results from our cross

pollination work. There is evidence, indeed, that for effective

fertilization, considerable heat is needed, but not the extreme

temperatures that occurred during this period.

In spite of the mild winter of 1951-52, the attacks of _Cryptodiaporthe

castanea_ (Tul.) Wehmeyer caused considerable twig blight, especially on

our crosses of _Castanea mollissimax seguini_. This is not surprising

since _C. seguini_ comes from a warmer region in China, but why these

attacks should occur during a mild winter is a puzzle. Evidently other

factors, such as the drought of the preceding fall, entered in.

Hybridization in 1951 and 1952

A total of 2400 hybrid nuts was harvested in the 1951 season and 1690 in

1952. This compares with the 1259 nuts reported for 1950. The increased

production over past years can in part be ascribed to a concentration of

the efforts on a fewer number of different crosses; while 103 were made

in 1950, the total was 77 in 1951 and 80 in 1952. The pollinations

followed the same general program in the two seasons, the emphasis being

on the Chinese x (Japanese x American) hybrids. This is our most

promising timber tree hybrid, and it seems worthwhile to test it on a

somewhat larger scale under forest conditions. Therefore, some of the

best early crosses have been repeated, new parent trees are being tried

and selected hybrids intercrossed. Back-crosses to the native chestnut

with the CxJA hybrids were made in an attempt to improve the form of the

hybrid.

Another cross which has attained some importance in the last years is

the hybrid between Japanese chestnut (forest type, from U.S.D.A.) and

S-8, the latter being a hybrid between Japanese chestnut and _C.

pumila_, the common chinquapin. This cross has a high degree of

resistance and a sufficiently good form to make it a possible timber

tree (Fig. 1). It is also a fairly good nut bearer with nuts which ripen

early, perhaps due to the influence of the chinquapin parent (Fig. 2).

Selected individuals of this hybrid were intercrossed, and some crossing

with the native chestnut was done.

In the last two seasons the total harvest from some older Chinese trees

(26 yrs.) was recorded. The best tree yielded 25.0 lbs. in 1951 and 28.2

lbs. in 1952; on other trees the yield varied between 15 to 22 lbs. The

average size of the nuts varies considerably from year to year on the

same tree. On one Japanese tree the average weight per nut was 5.6 g.

in 1951 and 14.5 g. in 1952; on a Chinese tree the same values were 7.7

g. and 15.1 g. Other trees showed a 20-40 per cent increase in the

average weight per nut in 1952 over 1951. This seems to indicate a

marked influence of the climatic conditions during the latter part of

the growing season on the weight of the nuts. A long-term study of this

relationship might yield some interesting results.

[Illustration: Fig. 1. Hybrid of S-8 and _Castanea crenata_, U.S.D.A,

forest type, 18 years old. About 35 ft. high. Good forest type and also

good nut bearer. Blight resistant. Sleeping Giant Chestnut Plantation,

Hamden, Conn. Photo by Louis Buhle, Brooklyn Botanic Garden. Sept. 26,

1952.]

[Illustration: Fig. 2. Fruiting branches and nuts of S-8 x _crenata_,

Sleeping Giant Chestnut Plantation. About 1/2 natural size. Photo by B.

W. McFarland, Conn. Agric. Expt. Sta. Sept. 8, 1952.]

Grafting

A considerable amount of grafting has been done since 1949 and the

results have been good. Two year old Chinese transplants are usually

used as rootstocks and all grafting is done in the field. The best

results have been obtained where the rootstock plant was transplanted

one year prior to the grafting. The simple splicegraft, or the bark or

rind graft are used, depending on the size of the scion compared to that

of the rootstock, the latter technique being used when the stock is

considerably larger than the scion. There is some evidence of

incompatibility; thus, scions from Chinese trees, or hybrids that show a

dominance of Chinese characters, give a higher percentage of takes when

grafted on Chinese rootstocks than scions from the native chestnut, or

from hybrids between Japanese and native chestnut. Some indications of

incompatibility between European and Chinese chestnut in grafts have

also been encountered where scions received through the cooperation of

Dr. C. Schad, Centre de Recherches agronomiques du Massif Central,

France, and Count F. M. Knuth, Knuthenborg, Denmark, were used, but in

some cases these grafts were successful. Topworking, using the veneer

crown graft, has been quite successful as long as sufficient sap drawers

are left on the stock (Fig. 3).

Inarching

The senior writer has already explained in detail (2) the simple method

by which blighted chestnut trees can be restored to health and vigor by

cutting out blighted areas in the bark, painting them over, and

inarching or ingrafting one or more basal shoots into the healthy bark

above the lesion. We do this work from mid-April to mid-May, and make a

systematic canvas of all the trees in all our plantations, inarching all

those where if is necessary or might be advantageous. Each operation

requires only a few minutes. Last year we put in many hundreds of

inarches, altogether, which later showed nearly 100% "take".

Owners of chestnut orchards should take advantage of this method of

keeping valuable nut-bearing trees, although with cankered areas, in

healthy, vigorous condition.

We believe that, in cutting out the diseased bark, it is advisable to

cut out also a few of the outer annual rings of wood (of course

tangentially), especially if the canker is one of long-standing, since

we know that the fungus eventually penetrates the outer rings of wood.

Since that is true, the canker might enlarge later on from this same

source of infection. Further it may also be possible for spores or bits

of mycelium to be transported upward in the sap stream and cause new

infections higher up in the tree. A thorough painting of the cut

surfaces should go far toward remedying this situation.

One can usually judge the extent of damage caused by the blight by the

number and vitality of the basal shoots, a large number of basal shoots

indicating a heavy attack. However, if the roots have been severely

injured, perhaps by short-tailed mice, as sometimes happens, no basal

shoots appear, in which case the tree is doomed.

If no blight is present, but one or more basal shoots appear (sometimes

due to shrubby ancestors), it is advisable to inarch these as an

insurance against possible trouble in the future.

This inarching process has not received the attention it deserves. There

is absolutely no reason why, if this method is followed, there should be

_any_ death from blight in resistant hybrids or in Japanese or Chinese

chestnuts, barring, of course, cases where roots are attacked by mice

(or _Phytophthora_ in warmer regions). Those of our trees in Connecticut

which have been blighted have continued in health and nut-bearing ever

since we began the inarching method in 1937 (Fig. 4). If the inarches

become blighted, they can themselves be inarched, as shown.

[Illustration: Fig. 3. Veneer crown grafting on chestnut. Photo by B. W.

McFarland, Conn. Agric. Expt. Sta. May, 1952.]

Research on Blight Resistance

[Illustration: Fig. 4. Japanese-American Chestnut, 21 yrs. old, showing

inarching begun 15 yrs. ago. Original trunk, long since dead and now

rotting, shows in center. Kept alive and vigorous because valuable for

hybrid vigor and future breeding. Sleeping Giant Chestnut Plantation,

Hamden, Conn. Photo by Louis Buhle, Brooklyn Botanic Garden. Sept. 26,

1952.]

A study has been made of the factors that cause the Chinese and Japanese

chestnut to be resistant to the Endothia canker, and a close correlation

was found between the tannin content of the bark and the relative

resistance of the three species, i.e., Chinese, Japanese and American

chestnut. The total tannin concentration in the bark of the Asiatic

species is only slightly higher than in the American, and native trees

can be found with as high a concentration as is found in the Asiatic. A

similar overlap in resistance does not occur and it is therefore clear

that the total tannin concentration as such cannot account for

resistance. There is, however, good evidence that the tannins in the

Asiatic species, as a result of the way in which they are bound to other

colloids in the cells, are more soluble than in the American species.

This, of course, would have a marked bearing on the effectiveness with

which the tannins could check the spread of the parasite. Furthermore,

it has been found that the types of tannins in the three species differ.

In the American and Japanese species they are a mixture of catechol and

pyrogallol tannins, while they appear to be pure pyrogallol tannins in

the Chinese species. Considering the specificity of the enzyme systems

of fungi it is quite possible that different tannins show different

degrees of toxicity to a certain fungus. The following hypothesis has

been suggested to explain the relative resistance of the three species:

In the American chestnut bark the concentration of the available toxic

tannin never reaches a level where it can stop the advancing parasite.

The tannins in the Japanese species, although of the same type as in

the native tree, are more soluble and reach a level toxic to the fungus.

In the Chinese trees all the tannins of the bark belong to the toxic

pyrogallol groups, and this, combined with their high solubility,

results in the high degree of resistance in this species (4).

The information available at present regarding the formation of tannins

in plants is not conclusive. In some plants, apparently, they are formed

in the leaves, and the presence of carbon dioxide and light is required;

in other plants the tannin concentration can increase when the plants

are grown in darkness (5). A more general formation of tannin in tissues

with a high metabolic rate throughout the plant has also been suggested

(3).

It would be important to know the centers of origin of the tannins in

the chestnut, their translocation, and whether they are translocated

through or over graft-unions. In other words, will a susceptible scion

when grafted on a resistant rootstock become more resistant because

antibiotic substances formed in the roots of the resistant rootstock are

translocated into the scion?

From a number of older grafts of non-resistant Japanese-American hybrid

scions on Japanese or Chinese rootstocks it appears that this indeed

might be the case. These grafts, some of which are 16 years old, appear

to be more resistant than the original hybrid tree, even if not as

resistant as the rootstock.

This would indicate the possibility that the antibiotic substances are

produced in the roots and translocated into the scion. However, the

possibility still remains that the compounds are formed also in the

leaves and translocated to the base of the tree. To clarify this whole

problem an experiment with Chinese-American grafts in different

combinations is under way. Preliminary results show that antibiotic

substances are formed in upper parts of the plants, but that they are

not translocated downward across the graft union. Thus it was found that

Chinese branches grafted on two year old American seedlings remained

resistant, without the American seedlings showing any increase in

resistance. In future experiments the upward translocation will be

studied in detail on grafts of American scions on Chinese seedlings.

Some Abnormal Conditions

1. _Sterility_

Sterility occurs quite commonly in interspecific hybrids either because

the chromosomes fail to pair in meiosis or because the parent genes when

brought together in the hybrid interact in some way deleterious to the

formation of sex-cells. Furthermore, cytoplasmic sterility is likely to

occur in a wide cross.

Sterility has been encountered in several instances in American x

Chinese and Japanese x American hybrids. In most cases it is a case of

pollen abortion only; either anthers fail to develop completely as shown

in Fig. 5, B, or the anthers develop but are much reduced in size and

contain no functioning germ cells.

Pollen sterility is not sporadic in a given individual: it is uniform

throughout the flowering branches. The individual flowers are

arranged on the catkin axis as in the normal flowers (Fig. 5). But

when the flowers open, a hand lens reveals 3-5 tiny, membranous

perianth-segments for each tiny flower, whitish in color, and more or

less connected at their bases. A minute rounded mass appears in the

center of the flower, perhaps primordia of abortive stamens, but this

does not develop further. The catkin begins to take on a brownish color

and at length the whole catkin, in case it is staminate, drops off. If

it is androgynous, the staminate part drops off, or withers.

These male sterile trees appear to have a normal, sometimes excessive,

development of the females, and are quite prolific nut producers.

Information on the occurrence of female sterility in the hybrid trees is

incomplete, but the indications are that at least partial sterility is

frequent.

[Illustration: Fig. 5. A. Normal androgynous catkin (female flower at

base); B. Androgenous catkin with sterile pollen. From Sleeping Giant

Chestnut Plantation, Hamden, Conn. Photo by Mary Alice Clark, Conn.

Agric. Expt. Sta. July, 1949.]

2. _Triploid Hybrid_

In 1934 we produced a cross of Chinese and American chestnut which

proved to be unusual in several respects. The leaves are enormous--9

inches to 1 foot in length, and 4 or 5 inches in width. The hybrid is

not particularly blight resistant but more so than its American parent.

It died back from the blight about 1940 and the present tree has

developed as a shoot from the old roots. The growth is rapid and

vigorous. The flowers appear normal, but we have never been able to make

a cross with its pollen, nor to effect fertilization of its pistillate

flowers. It may be triploid, that is, with 3 sets of chromosomes instead

of the normal double set, and this would account for its barrenness.

In the spring of 1952 some of the vigorous shoots of this tree were

successfully grafted on shoots from an old stump of Chinese chestnut,

using the veneer crown graft method. The scions had not been taken when

dormant, but were transferred directly from the tree to the stock in

late April. This grafting was done in order to impart greater

resistance, if possible, to the CA hybrid by means of the roots of the

Chinese stock.

3. _Systemic Defect_

Since the early 1930's we have seen occasional individuals with abnormal

foliage--somewhat mottled, usually curled and often misshapen. Thinking

that a virus might be the cause of this trouble the senior author tried

grafting some of the shoots on to healthy stocks. The grafts were in no

case successful because the scions were too weak. Finally he succeeded

in grafting a branch from an affected tree on to a branch of a normal

individual. The only result was an increased vigor of the healthy

branch. This year he rubbed juices from leaves of such an abnormal

individual on to wounded healthy leaves, without result. Moreover, such

sick individuals, although growing for years close to healthy trees,

have never communicated the malady to their neighbors. Growth is

comparatively slow, and there is much dying back or dying out of the

slender branchlets.

The evidence indicates that this is _not_ a virus trouble, but a

systemic defect, probably caused by chromosome aberration or gene

abnormality. It is significant that this trouble occurs only in hybrids.

Such trees never flower. We have known four such cases, two of which are

now dead. Similar types appear in other species as inherited deviations

from normal.

Insect Injuries

A heavy attack from the spring canker worms developed in 1951, but

spraying with DDT on May 24th prevented serious damage. No outbreak of

canker worms appeared in the spring of 1952. The Japanese beetle has

been very little in evidence. The principal bad actors are the mites,

_Paratetranychus bicolor._ Although barely visible to the naked eye, the

effect they produce of whitening the leaves is conspicuous, especially

on the Chinese chestnut and its hybrids. These insects overwinter in egg

form on the surface of the bark. Last winter they were so numerous on

some of the trees that the bark had taken on a red color--especially on

smooth-barked trunks just below a branch. An application of "Scalecide"

on April 21, while the trees were still dormant, followed by two heavy

applications of "Aramite" (6-7 lbs. per acre) on June 13th and 27th,

gave good control for the rest of the summer. Spraying with DDT for

weevils was done on August 18th and September 3rd in 1952 with good

results.

Cooperative Hybrid Chestnut Plantations

In 1947 the first hybrid chestnut plantation under forest conditions was

made in cooperation with the U.S.D.A. Bureau of Plant Industry, Division

of Forest Pathology. The plantations are made in order to test the

hybrids under normal forest conditions and different climatic

conditions. In general, each plantation consists of about 100 trees, 50

U.S.D.A. hybrids and 50 Connecticut hybrids. The trees are planted at a

10' by 10' spacing, and the overstory is girdled at the time of planting

in order to give the plants better light conditions without causing an

abrupt change in the microclimate of the forest floor--a method

developed by Dr. J. D. Diller of the Division of Forest Pathology (1).

Ten plantations at 9 locations have been established since 1947. These

are listed below:

No. of Plots Location Year Established

-------------------------------------------------------------------

1 Edward Childs Estate, Norfolk, Conn. 1947

1 Tennessee Valley Authority, Norris, Tenn. 1947

1 Table Rock State Park, Pickens, S.C. 1948

1 Antioch College, Yellow Springs, Ohio 1948

1 Upper Perkiomen Valley Park, Green Lane, Pa. 1949

1 So. Ill. Univ. Fish & Wildlife Service, Cartersville, Ill. 1949

1 Russ State Forest, Decatur, Mich. 1951

2 Nathan Hale State Forest, Coventry, Conn. 1951

1 Ouichata Nat'l. Forest, Hot Springs, Ark. 1952

-------------------------------------------------------------------

Connecticut State Ownership of Sleeping Giant Plantations

On April 11, 1951, at a meeting at the "Little Red House", Sleeping

Giant Mountain, the lands on the Sleeping Giant Mountain, Hamden,

Connecticut, about 10 acres, on which about 1500 chestnut trees are now

growing, including nearly every chestnut species known to science, and

many valuable, blight resistant hybrids, were formally deeded over to

the State of Connecticut by their owner, the senior writer of this

report. The meeting was attended by officials of the Sleeping Giant Park

Association, the Connecticut State Park and Forest Commission, The

Connecticut Agricultural Experiment Station, and the Yale School of

Forestry. The transfer to the State was made with the understanding that

The Connecticut Agricultural Experiment Station would continue the

chestnut breeding work. The whole region is now undergoing a fairly

rapid housing development, and in the ordinary course of mortal events

this plantation would have been divided into building lots within the

next few decades. The State ownership will obviate this, and The

Connecticut Agricultural Experiment Station sponsorship will assure a

continuation of the breeding work.

Literature Cited

1. Diller, J. D. Growing chestnuts for timber. 37th Ann. Rept. of

Northern Nut Grower's Assn. for 1946. 66-68. 1947. 2. Graves,

Arthur Harmount. A method of controlling the chestnut blight on

partially resistant species and hybrids of _Castanea_. 41st Ann.

Rept. of Northern Nut Growers Assn. 1950. 149-151. 1951. 3. Hauser,

Willibald. Zur Physiologie des Gerbstoffes in der Pflanzenzelle.

III. Protoplasma 27:125-130. 1936-37. 4. Nienstaedt, Hans. Tannin

as a factor in the resistance of chestnut, castanea spp., to the

chestnut blight fungus, _Endothia parasitica_. Phytopathology

43:32-38. 1953. 5. Nierenstein, M. The natural organic tannins. J.

& A. Churchill.

FOOTNOTES:

[Footnote 18: Also of The Division of Forest Pathology, U.S.D.A., Plant

Industry Station, Beltsville, Maryland.]

[Footnote 19: Records furnished by the U.S. Weather Bureau at New Haven,

Conn.]

[Footnote 20: October, 1952, was among the six driest Octobers on

record. These were: 1879, 1892, 1897, 1916 and 1924. From U.S. Weather

Report, New York City.]

Effect of Vermiculite in Inducing Fibrous Roots on Tap-Rooting Tree

Seedlings

HERBERT C. BARRETT[21] and TORU ARISUMI[22]

When seedlings of nut trees and other tap-rooted species are

transplanted from nursery to orchard, the percentage of survival in

often quite low. Perhaps the chief reason for this failure is the marked

and pronounced tendency of most tap-rooted plants to produce little or

no fibrous, branched roots in lieu of the long, straight, and seldom

branched tap roots.

The common practice of undercutting seedlings during the dormant season

to induce a branched root system requires additional labor, and often

results in reduced growth and vigor during the following season. The use

of hardware cloth or other close-meshed wire is effective, but this

method also has the disadvantage of being relatively expensive for the

nurseryman.

Preliminary work carried on during the past two years has shown that

with certain nut trees and other tap-rooted plants, it is possible to

induce fibrous roots by growing such seedlings in vermiculite. The

methods and results of this work are presented in this paper.

Material and Methods

Seeds of black walnut (_Juglans nigra_), Persian walnut (_Juglans

regia_), Chinese chestnut (_Castanea mollissima_), pignut hickory

(_Carya glabra_), shellbark hickory (_Carya laciniosa_), shagbark

hickory (_Carya ovata_), pecan (_Carya illin_), pawpaw (_Asimina

triloba_), and three persimmons (_Diospyros kaki_, _D. lotus_, and _D.

virginiana_) were stratified in moist sawdust for three months at a

temperature range of 35 to 40 degrees F. After this period of

stratification the seeds of each species were divided into three lots

and planted in flats 25 x 26 x 6 inches containing one of the following

media: (1) sharp sand of the type used in potting soil, (2) potting

soil, and (3) vermiculite. Seeds were kept moist with ordinary tap water

and allowed to germinate and grow in the greenhouse. When the seedlings

had grown two or three true leaves, they were carefully removed from the

medium and examined for the type of root system developed.

Results

In the first eight species listed in Table 1, the differences between

branched and tap-rooted seedlings were quite pronounced. The few

tap-rooted seedlings growing in vermiculite medium showed some laterals

and were less strongly tap-rooted than those in soil or sand. Pawpaws in

soil and sand media were practically devoid of laterals, and their

fibrous root system in vermiculite was not as pronounced as with the

walnuts, hickories, and pecans. Of the species studied, the persimmons

Table 1.

Sand Soil Vermiculite

Species Number of plants

Tap rooted Fibrous Tap Fibrous Tap Fibrous

Black Walnut 20 3 24 2 0 39

Persian Walnut 15 2 13 1 0 15

Chinese Chestnut 35 6 32 7 3 37

Pignut Hickory 19 0 22 0 3 16

Shellbark Hickory 9 0 8 0 0 13

Shagbark Hickory 27 0 25 0 2 28

Pecan 21 0 23 0 0 15

Pawpaw 102 0 140 0 20 85

D. kaki 6 2 5 3 0 10

D. lotus 20 11 18 7 0 30

D. Virginia 16 0 20 0 0 14

showed the least tendency to produce tap-rooted seedlings. Typical

branched or fibrous-rooted seedlings grown in vermiculite are

illustrated in Figure 1.

[Illustration: Fig. 1. Seedlings grown in vermiculite medium. Left,

_Juglans regia_; right, _Castanea mollissima_.]

Summary

The chief difficulty encountered in transplanting several nut tree and

other commonly tap-rooted seedlings is thought to be due to the lack of

a branched root system. The methods and results of a fairly simple

technique of inducing fibrous roots, that of growing seedlings in

vermiculite, have been presented.

FOOTNOTES:

[Footnote 21: First Assistant in Plant Breeding, University of Illinois,

Department of Horticulture.]

[Footnote 22: Formerly Half-time Assistant in Plant Breeding, University

of Illinois, Department of Horticulture.]

Eastern Black Walnut Survey, 1951

H. F. STOKE, _Roanoke, Va._

The Northern Nut Growers Association, at its 1950 Annual Meeting,

adopted a resolution directing that a survey covering the eastern

American black walnut, _Juglans nigra_ be conducted during the ensuing

year, and that the services of the State and regional Vice-presidents be

utilized in making the survey.

In carrying out this mandate fifty questionaires were sent out, and 37

replies were received. Of these, 33 were from the States, including the

District of Columbia, three were from Canada, including British

Columbia, Ontario and Prince Edward Island, respectively, and one was

from Belgium.

From these replies, as compiled, it is apparent that the natural range

of the American black walnut may be defined approximately as follows:

Beginning at the Atlantic seaboard at Massachusetts Bay curving slightly

northward then westward across northeastern New York to Toronto and on

westward across lower Ontario, Lake Huron, Michigan, Wisconsin and

Minnesota, in which state the line curves south-westward, crossing about

the northwest corner of Iowa. From this point the line runs

approximately south across the eastern parts of Nebraska, Kansas,

Oklahoma and Texas. As the line approaches the Gulf of Mexico it turns

eastward, crossing the southern parts of Louisiana, Mississippi, Alabama

and Georgia, back again to the Atlantic.

The natural range of the black walnut may be said to have been limited

on the north by winter cold, on the west by lack of sufficient rainfall

and on the south by a winter climate too mild for the required dormant

rest period. Where these limitations are removed the American black

walnut appears to do well far out of its natural range.

In its native state it seemed to thrive best along water-ways and in

hollows among the hills and mountains, though it was also to be found on

the uplands wherever the soil was fertile and other conditions

favorable. The overflow of streams undoubtedly did much to distribute

and plant the seed, aided always by the ubiquitous squirrel.

Twenty-nine of the States reported the trees as thrifty and bearing

well-filled nuts. Eastern Maryland reported the trees as thrifty but the

nut crop light. Michigan reports the nuts as having been well filled

formerly, but poor in recent years. West Virginia makes a similar

report, and attributes poor crops to the presence of anthracnose, a

fungus disease of the leaves causing early defoliation.

The nut crop of the wild trees appears to be ungathered to a large

extent, taking the country as a whole.

Eleven states report whole husked nuts being marketed in a limited way

and six report the marketing of home-produced kernels. Prices for the

whole nuts are quoted as low as $2.00 per bushel, with a top of $5.00

per bushel for Kansas-produced named varieties.

Accurate statistics as to whole nut and kernel production are not

available.

Tennessee reports black walnut cracking plants, as follows: One each at

Lebanon and Morristown, and three located at Nashville.

A West Virginia report estimates the State's kernel production at

$200,000 per annum. A cracking plant in St. Louis is reported as

processing 1-1/2 million pounds of whole nuts annually, for which it

pays 5-1/2 cents per pound. Other cracking plants reported are one at

Stanford, Kentucky, one at Broadway, Virginia and one or two in West

Virginia, location unstated. No statement was received as to the amount

of business done by these. A new one is starting operations at

Henderson, Kentucky in 1951.

Production of black walnut kernels as a home industry has languished

since the Federal ruling that the kernels must be pasteurized as soon as

produced. Most of such kernels are now consumed locally, so as not to

run afoul of inter-state regulations. No epidemic has, as yet, been

traced to such local use.

A question designed to disclose what named varieties give the best

results in the various localities was not very effective. Replies

usually came in the form of lists of varieties being planted with little

definite indication as to the ones that have proven superior.

As might be expected, Thomas led the list by being mentioned 15 times.

Elmer Myers was listed 9 times, Stabler 6, Ohio 6, Mintle 3, Snyder 2,

(New York and Tenn.), Sifford 2, (Kentucky and Kansas), and the

following one each: Adams, Grundy, Korn (Michigan); Rohwer, Vandersloot

(Kansas); Sparrow, Victoria, Homeland (North Carolina); Ten Eyck (New

Jersey); Creitz (Virginia); and Impit (British Columbia).

A study of the geographical distribution of the preferred varieties

fails to produce any significant conclusions as to the varieties best

adapted to any specific state. Doubtless Thomas heads the list because

it has had the longest and largest distribution. A New York state survey

gave Thomas the preference 9 times, Snyder 7, Myers 4, Ohio 2, and one

each to several other varieties. A similar survey in New Jersey gave

Thomas preference 2, Stabler 2, Ten Eyck 1 and Ohio 1.

One New Jersey correspondent reported Ohio as "excellent", another

listed Ten Eyck as "fair", and a third reported Thomas as "terrible".

One Kansas producer reports Thomas his best and Ohio his worst. Another

Kansan reports the exact opposite.

Pennsylvania reports Ohio as best, Stabler as worst. Her neighbor to the

east, New Jersey, rates Stabler highly, as does Ohio, immediately to the

west.

The notable leaf-disease resistance of the Ohio variety is worthy of the

consideration of planters in districts where early defoliation causes

poor filling of the nuts.

For a late comer, the thin-shelled Myers makes a strong showing, which

may be significant. It is worth watching.

Until there is wider planting and production of the named varieties, it

will not be possible to name the varieties best adapted to any specific

state or location, in the opinion of your reporter.

The possibilities of profit in planting black walnut orchards have not

been determined.

From Pennsylvania comes the report that of the several black walnut

orchards planted twenty-five years ago, only three are now being given

care.

A ten-acre orchard at Wharton, Md. that, presumably, was being given

special care, is reported as nearly all dead--"too much commercial

fertilizer, or the wrong kind."

The report on several small West Virginia plantings is submitted as

"inconclusive".

The main general interest at present appears to be the planting of the

better walnuts on home grounds and on the farm. Twenty-four states

reported such use, with varying degrees of interest.

Considering that the black walnut is our finest cabinet wood, and one of

the best in the world, forestry planting may be truthfully said to be

lagging deplorably.

The state of Pennsylvania has shown some interest and made some small

plantings.

Ohio has done some planting. The Sunny Hill Coal Company of New

Lexington, Ohio, is reported to have planted 5000 seedlings.

In Indiana Ford Wallick has reported the planting of 14 bu. of seed, the

seedlings to be budded later to the Lamb curly walnut. Tennessee and

West Virginia report small plantings.

Kansas reports some interest in planting walnuts on lands that have been

destroyed for agricultural purposes by strip coal mining.

As a whole, the forestry plantings of the walnut of the future, as of

the past, appear mainly dependent on the untiring squirrel.

There has never been an adequate supply of walnut timber since pioneer

days when walnut logs were rolled together for burning in the clearing

of land, or split for fence rails, nor is an adequate supply in sight

for the future.

In producing districts buyers are always ready to pounce on the owner of

any walnut tree of marketable size. Prices paid are usually much lower

than the real value of the timber, partly because the stand is so

scattering as to prevent the use of efficient means of logging and

transportation.

Of all the agencies tending to destroy the black walnut, war is the most

devastating. The superb qualities of the wood for the making of gun

stocks causes the country to be combed more and more closely by buyers

in each succeeding war.

However, from the standpoint of human interest, the picture is not

wholly dark. It is perhaps too much to expect that private enterprise

will enter into the long-time investment necessary for extensive

forestry plantings, but the states can and should do so in connection

with their park and forestry programs. As already indicated some few

states are working in that direction.

Of perhaps more immediate concern and value are the possibilities of

interesting the 4-H clubs and similar organizations of youth in making

home and farm plantings. Refreshingly encouraging is the following

excerpt from the report of the Arkansas state Vice-president, Mr. A. C.

Hale, a vocational instructor of Camden, Arkansas.

"When a student comes into the class of vocational agriculture in the

ninth grade I try to get him to plant some black walnuts so they will

get big enough to graft while he is in high school. The use of this

method is helpful in getting many trees started. By grafting one or more

of the Persian walnuts, interest is also added."

"One way that has helped me get people started with a tree on the home

grounds is to pot a few sprouted nuts and when a neighbor is sick take a

seedling walnut instead of a flower. I usually go back to help with the

transplanting of it."

Such practical methods, if widely used, would bring far more valuable

results than any legislative program.

The Virginia Polytechnic Institute is showing some interest, and

conducted a field clinic in top-working the walnut in the Shenandoah

Valley area in the spring of 1951. County Agents have become interested,

and a county-wide Black Walnut Contest will be held at Harrisonburg,

Va., Nov. 9 and 10th of this year, in which VPI is collaborating. It is

hoped this idea will spread.

On Prince Edward Island, just off the Canadian east coast, there does

not appear to be enough summer heat to mature the nuts, though the tree

is grown somewhat on home grounds.

In the fruit-growing sections of British Columbia the black walnut

appears quite at home, trees of a diameter of from three to four feet

being reported at Chilliwack, in the Fraser River valley. J. U.

Gellattly also reports the walnut at Brooks and Medicine Hat, Alberta.

Confirmation of the ability of the black walnut to stand extremely low

temperatures is to be found in a letter of Aug. 22, 1951 from W. R.

Leslie, Superintendent, Dominion Experiment Station, Morden, Manitoba,

as follows:

"Black walnut is doing fairly well in such places as the Provincial

Horticultural Station, Brooks, Alberta, (P. D. Hargrave, Supt.), and at

Portage la Prairie, Winnipeg and Morden, Manitoba. Apparently the black

walnut enjoys a heavier soil than the butternut (or white walnut). The

white has been more widely planted than the black. The Manchurian seems

hardier than either and is the most rapid grower of the three _Juglans_

on test here. However, the two natives usually give us a fairly abundant

crop of nuts."

"Our source of black walnut was from around New Ulm, Minnesota; the

butternut came from around Sault Ste. Marie, at the lower end of Lake

Superior. I am not aware of either indigenous species being native

closer than the points mentioned."

Belgium reports the black walnut as thriving in door-yards and along

roadways, where the nuts are mentioned as a menace to traffic.

In conclusion it is urged that friends of conservation and a sound

economy should lend their every effort to the extension of black walnut

plantings. Some progress has been made since the days of pioneer

plunder, but much remains to be done.