refractory engine that will suddenly sputter, there came some elements
of success. The point to learn was, why? Concentrating on the shield bud
entirely we determined to find these whys. So we tried taking big slabs
of bark along with the bud, peeling out the wood, breaking off the leaf
stem entirely and waxing the scar and making an unnecessarily long cut
for the bud. The bark stuck fairly well but the buds died. This was some
encouragement and I knew that with enough time, reason and a little luck
we would eventually hit the mark.
Now Dame Fortune had decreed that I be raised on a grain and stock ranch
where the only trees we could see were in the distant mountains, or, if
we rode in the canyons, cottonwoods and choke-cherries. My experience
and training was with animals, and animals, especially horses, seem
quite susceptible to accident. The first principle of treating almost
any wound is to give it drainage, otherwise, both literally and
figuratively, the "sap" soured. Thus it dawned on me that a tree-wound,
even if only skin deep should have the same treatment as a flesh wound.
And drainage, being desirable, should be ample.
It was quite late in the season but I went out and set a dozen Schafer
walnut buds on eastern black stocks. These buds HAD DRAINAGE. The
vertical cut of the T extended at least two inches below the bud.
Success ensued, they grew. The following spring we budded as soon as the
bark would slip and continued at intervals all summer. Results were
good. Some of the steps we now use are probably not essential and
perhaps not even the best, but there are two points that cannot be
over-emphasized, namely, drainage and contact. The complete method is as
follows: 1. Trim bud sticks to leave an inch of petiole on the bud. 2.
Make the T cut with a long vertical slash that will extend at least an
inch below the bottom of the bud. 3. Cut the bud long and deep and peel
it from the wood by pinching the sides. Be carefull not to injure the
bark just below the bud. 4. Insert the bud either flush with or below
the cross-cut. 5. Wrap with large sized rubber budding strips just
firmly enough to make good contact. Too tight wrappings curtail
circulation. Do not cover the cut below the bud. The wound must have
=drainage=. 6. Be sure that the center of the bud-cut is firm against the
cambium layer. If it humps of bows and won't stay down insert a
tooth-pick or bit of leaf stem or something along the center line to
hold it down. We usually do this during the wrapping process.
We use no wax. We throw a wrap over the bud, shoulders even though it
may press the petiole forward against the bud. If the center of the bud
pulls out it will not grow although an adventitious bud may eventually
start. Budding seems about equally successful any time that the bark
slips freely. On walnuts this is all summer if not too dry.
Early-placed buds may make several feet growth before fall if sufficient
moisture is available. On walnuts there are always dormant buds. We have
used storage wood but now just cut it fresh. We have not tried draining
patch-bud or grafts. Although we have not tried it we think cherries and
other trees inclined to drown the buds might be better handled in this
manner. Climate is a factor in the type of propagation advisable. One
very fine grower using buds in California could propagate only by grafts
when he moved to Western Oregon.
The kernel of my walnut budding experience may well be summarized in one
word--drainage.
* * * * *
Questions asked Mr. Stoke after his demonstration of grafting and
budding. [See his paper in 1946 Report, pp. 99-103.--Ed.]
Member: "How do you keep your scions?"
Stoke: "I prefer 'orange' cold storage for scionwood. This is just above
freezing. Walnuts should be in full leaf before spring budding."
McDaniel: "What percentage of chestnuts did well with the 'plate' method
of budding?"
Stoke: "I don't use it with chestnuts for spring budding, but sometimes
for summer budding. It will work well on any variety of Persian walnut,
heartnut and black walnut. Place buds on the north and northeast side of
tree to prevent sun injury."
Question: "Do you find any difference in using buds from an eight or ten
year old tree as against a younger tree?"
Stoke: "No, not so long as it is healthy. For spring budding I don't
care to have any trees too vigorous. Cut tops off young trees three to
five days after budding, and force the buds into growth. If you delay
too long the bud will die. I wouldn't try to bud trees unless bark is
slipping."
Member: "I have used parapin wax and covered it with old bread paper."
Stoke: "That may work because the wax was shaded. Southern sun may melt
parapin and paraffin waxes."
Mr. Corsan: "Dentists, surgeons and wood carvers make the best
grafters."
Question: "Can the scions be cut with a small plane?"
Stoke: "Anything you have to cut with a plane is too big. I never use a
plane."
Question: "What do you use a splice graft for?"
Stoke: "Anything except walnut. In walnut I use a modified cleft graft,
and I take care of the sap flow by placing the graft down about 1" or
1-1/4" below the cut (where the tree is cut off). Wax the scion but do
not wax the cut. Let it bleed."
Question: "What is the value of cut leaf black walnut?"
Stoke: "Purely ornamental. Weschcke reports that it is very hardy with
him."
Rick: "What about the Lamb walnut?"
Stoke: "We don't know whether the wood of grafted trees is curly or not.
I sent Mr. Reed a limb from Lamb and he gave it to the forest laboratory
and they found no evidence of curly grain."
Rick: "Shouldn't it be propagated until we are sure?"
Stoke: "We had Mr. Lamb himself talk before us at Roanoke and he told us
about the parent tree. He doesn't know what makes one tree curly and
another not."
Korn: "Is that uncommon?"
Stoke: "Not so very. Trees are most curly at the base and in the outer
wood."
Question: "Do you always leave that stub on black walnut?"
Stoke: "Yes, but it should be removed later in the first summer."
Question: "Where do you use your splice graft."
Stoke: "On anything other than walnut, if scion and stock are the same
size. Where stock is larger than scion I use the modified cleft graft up
to sizes approaching one inch in the stock. For topworking larger stocks
I use one of the forms of bark graft. For the large hickory stock Dr.
Morris' bark slot graft is preferred. For large, thin-barked stocks the
simple bark graft may be used. My original grafts of the Carr and Hobson
Chinese chestnuts, made with scions received from Messrs. Carr and
Hobson in the winter of 1932, are still perfect unions.
"I believe that grafted chestnuts growing in frost pockets are most
likely to develop faulty unions; possibly frost injury to immature cells
at the junction point may occur. Dr. Crane mentions a similar failure of
unions between Persian and black walnuts on the Pacific Coast."
Dr. Crane: "What cut did you use in grafting those chestnuts?"
Stoke: "Modified cleft. In using Dr. Morris' bark slot graft I find it
best to leave just a little of the cut face of the scion wedge above the
top of the stock. This, with top of the stock cut sloping away from the
scion, as illustrated, promotes quick healing with no 'die-back.'"
Dr. Smith: "Is that top slanting?"
Stoke: "Yes, I cut it slanting."
Dr. MacDaniels: "That is a good graft for walnuts, too."
Note: Mr. Stoke showed the group a picture of a mockernut tree in one of
his fields which he had girdled to kill it. The tree lived four years
and during those years the moisture had to go up through the inner wood.
The substance of Mr. Stoke's talk, together with illustrations, may be
found on page 99 of the 1946 report.
Importance of Bud Selection in the Grafting of Nut Trees
G. J. KORN, Kalamazoo, Michigan
For many years the fruit growers have been improving the qualities of
their fruits in several ways. The early pioneers of our country selected
the best fruits from seedling trees. Chance seedlings that were found in
pastures, by roadsides, or possibly in some out-of-the-way place,
selected because of some special quality or group of qualities, still
dominate our commercial plantings of fruits and nuts. Several of the
apple varieties to be found in the market today are from these chance
seedlings.
In more recent years some of our agricultural colleges have been
breeding fruits. Such breeding has given us several of our more
promising named varieties. In this way a great improvement has been
brought about in our fruits.
Environment too appears to have played an important part in making
changes in fruits and nuts. Nuts that are extremely hardy in the more
northern latitudes, appear to have developed this hardiness gradually
throughout many generations. Because of this quality we are now able to
select varieties that are most likely to succeed in any particular
locality.
More rapid and satisfactory methods of improving our fruits and nuts
have been brought about through breeding. This development of the
science of plant breeding has made it possible to blend the good
qualities of two seedlings into a new variety. Man does not have to
follow nature's slow hit-and-miss method of developing more desirable
qualities in her products. Controlled breeding, as brought about by man,
produces faster and more satisfactory results. Man's improvement over
nature has come about through his choice of the qualities to be blended,
and his ability to bring together two parents from widely separated
parts of the earth, if necessary.
Besides breeding, we are able also to use some of the mutations or bud
sports to improve our nuts as well as fruits. Although our progress in
improving nuts may not yet be as spectacular as cross-breeding with
apples, bud selection has already modified the list of our commercial
varieties.
One of the first requisites in bud selection is so thorough a knowledge
of the variety that any departure from the type will be detected. Then
it will be necessary to start propagation to determine whether the
variation was caused by some environmental factor, or is really a sport
which can be perpetuated by vegetative propagation. You may wonder if
many of our nut growers know nut varieties well enough to detect any but
the most obvious sports. Nut improvement through bud selection within
the variety lies ahead of us.
Among fruit growers the search seems to have been for fruits of
different or more pleasing color. As nut growers we are more likely to
be interested in nut sports having better size, kernel, cracking
qualities, etc. Trees that are able to ripen their nuts in short or cool
seasons are especially desirable in some of our more northern states.
My attention was especially called to the importance of bud selection
several years ago while buying my winter's supply of apples. I was
examining the splendid crop of Jonathan apples in a neighbor's large
commercial orchard. On most of the Jonathan trees the apples were large
and well colored and the crop was heavy. However, a few trees bore
apples of inferior size and color. Upon questioning the fruit grower as
to the difference in the performance of the two types of Jonathan apple
trees, he explained that the better apples came from trees supplied by a
nurseryman who was very particular in selecting a good bud strain. The
other trees were just the ordinary strain of Jonathan.
It was while working in a commercial orchard of the grafted varieties of
black walnuts that I noticed one especially promising Thomas tree.
During the few years that I have observed this tree, its nuts have been
of splendid size and very uniform. The kernels from the nuts from this
tree were somewhat better than those from most of the other trees. I now
have some grafts growing from this promising tree.
There appears to be much promise for nut improvement by cross-breeding
to regroup desired qualities. Although many of us enjoy the nut contests
that are conducted from time to time, it appears that our nut
improvement program might move along faster if more attention were given
to nut breeding and searching out desirable bud sports.
Discussion after G. J. Korn's paper.
Corsan: "Farmers should be encouraged to plant nut trees along boundary
lines. Enormous amounts of fertilizer there."
J. R. Smith: "One tree in ten thousand seedlings is worth while."
Dr. Lounsberry: "We have two trees planted close together--one bears
small nuts and the other large nuts. They are from the same grafting. It
would seem that the trouble is in the stock. The stock makes a vast
difference."
The Hemming Chinese Chestnuts
E. SAM HEMMING, Easton, Maryland
The bearing record of our row of 18 Chinese chestnuts has attracted so
much attention that I thought the Association would be interested in
seeing some slides of these trees, also of our experimental orchard, as
well as the large quantity of small trees we grow in our nursery and the
manner in which we raise them.
You will see a number of slides of chestnut trees and hear a lot about
the bearing qualities, but you won't see a single nut, for unfortunately
all these slides were taken between December 1946 and July 1947. You
will just have to let the numerous little trees attest to the fact that
these trees bear. We have 50,000 trees in our nursery.
These trees are now nineteen years old and have borne rather remarkably
since 1937. They are spaced too close--an accident--but I believe that
helps thorough pollination. They are now 12 and more inches in diameter,
some are 30' high and the spread is at least 35' where they have the
room. All but No. 14 are spreading in character; spreading character and
good bearing seemed to be connected.
The bearing record of these trees has been given before but I will
summarize them by years again: 1937--118 pounds; 1938 (no records);
1939-463 pounds; 1940--250 pounds; 1941--564 pounds; 1942--658 pounds;
1943--749 pounds; 1944--678 pounds; 1945--250 pounds; 1946--1,100
pounds; this year's crop will probably run 700 to 800 pounds.
The trees seem to bear much the same, with No. 14 the poorest and No. 19
the best and, like many other tree crops, they tend to alternate good
and poor crops on each tree. The nuts are of good size, averaging 40 to
50 per pound (green) with No. 6 and No. 19 bearing the smallest nuts.
They ripen in September with the exception of No. 19 which is a month
later. Mr. Reed likes No. 16 which has a wrinkled shell. All the nuts
are medium sweet to sweet and all of them fall free of the bur. I think
the most significant thing is that at least 12 of the trees have nut
characteristics so near alike that they are about indistinguishable,
which certainly makes them a good source of seed.
The similarity of the nuts brings up the controversial subject of the
seedling raised tree, and I will make some remarks in defense of this
method.
1. All our parent trees are good bearers.
2. There is no extraneous pollen in the vicinity.
3. I will present as a question: Has the Chinese chestnut, like the rose
and the apple been hybridized out of all semblance of the wild form?
4. The seedling tree should bring chestnuts to the average householder's
table 30 years sooner than grafting will.
5. We now produce a 3'-4' tree for a very reasonable figure.
6. All varietal forms at present are as yet unstabilized (most varieties
of 10 years ago have been discarded). There will probably be some duds
in seedling trees, but we've had no local complaints and I wonder if
they will exceed the "troubles" found in the grafted tree. We have had
customers brag about what their 2 or 3 or 6 trees bore.
To prove our faith in this method we planted a test orchard. When the
trees were 3 years old from 2 year transplants they bore 25 pounds. Next
year, 1944, they bore 800 pounds or an average of 1 pound per tree.
Right then and there we thought that we would have a real story to tell,
but we had misfortune in another direction. Three years in a row we have
had frosts when 6 inches of new growth were on these trees (the orchard
is not as well situated as the parent trees in this respect). So we had
no crops worth mentioning but neither did we have strawberries or
similar fruits. This year the orchard was frosted 2/3 the way to the top
so we will get quite a few nuts, maybe 500 pounds. Incidentally, we have
been here 25 years and we've not had frosts like these before.
We use all of our good nuts for seed purposes, grading out all small or
damaged nuts. In raising these trees, even from seed, we've had our
troubles. We let them cure several weeks then plant them in well fed
soil in a narrow trench about 2 inches deep. We place the nuts 5 or 6
inches apart; we fill the trench with sawdust level with the surface. We
mound the soil over this about 4 inches until spring. Then it is
removed. This method lets the shoots through, otherwise they tend to
send 3 or 4 stems. The nut sends down the root very early in the spring.
We have some trouble with the mole-mice combination; for this reason
heavy soil and sawdust is better than sandy soil. As you know neither
the nut nor the tree likes wet soil.
In raising the young tree the principal difficulty is in getting a
trunked upright tree. A seedling, especially when transplanted the first
year, flops all over like a flowering shrub. To get them up we plant
them fairly close, prune them, and feed them. Our 1 year trees are
usually two feet high and 2 year trees are 4 to 5 feet high. We
wholesale our trees mostly to mail order nurseries and the largest had a
5% request for replacements.
There are troubles in growing Chinese chestnuts just as there are in
most fruits and nut crops and, in a way, I am glad there are because I
am of the opinion there is no such thing as harvesting without
cultivation. For instance, if you plant them and let nature take its
course--it will. It will on an apple, too.
We have found a few small lesions of chestnut blight which were removed
by pruning and then painted with pine tar. They usually occurred at a
previous point of pruning. Some of the transplanted seedlings have
developed a twig canker at a bud, but I've never seen them kill one and
even when we don't prune it out, the tree overcomes it by new growth.
The Japanese beetle attacks the chestnut but, although they were bad
this year, one spraying of DDT was effective. The weevil (curculio) was
bad enough last year so we are spraying this year. Small growers should
put the nuts in metal containers and thus destroy the larvae, if any.
I would like to remark here that we are a nursery growing many
ornamentals, and the Chinese chestnut, although low branched, is a very
ornamental tree. I know of no tree that has a handsomer dark, shiny
green leaf or one whose green color holds so well until frost.
Now I think you will agree I have reported the behavior of our trees
fairly, the difficulties of raising the trees, and have emphasized that
I doubt if you will get success with the Chinese chestnut without
effort; yet in conclusion I would like to step into "fantasy". Our No.
19 tree bore 124 pounds; suppose you had 50 trees per acre bearing that
quantity. You would get 6,000 pounds per acre. The European chestnut,
which is not as good, brought 30c on the Baltimore market last year.
That would mean $1,800.00 per acre. Imagine having 10 acres!
1947 CROP
Pounds of Chestnuts from Original Trees at Eastern Shore Nurseries, Inc.
No. 1, 78; No. 2, 58; No. 3, 51-1/4; No. 4, 7-1/2; No. 5, 49; No. 6, 31;
No. 7, 34; No. 8, 31-1/2; No. 9, 63; No. 10, 40-1/2; No. 11, 61-1/2; No.
12, 64-1/2; No. 13, 56; No. 14, 47-1/2; No. 15, 74; No. 16, 60; No. 18,
106; No. 19, 25-1/2--Total, 938-3/4 pounds.
=Young Orchard:= 225-1/2 pounds.
Discussion after E. Sam Hemming's paper
Corsan: "Do you recommend the use of lime?"
Hemming: "We do not use lime. We use Vigoro at the rate of 1 to 1-1/2
lbs. to inch of diameter per tree."
Corsan: "Why do you use Vigoro?"
Hemming: "No particular reason, just that it is available."
Member: "What time of year do you fertilize your trees?"
Hemming: "We fertilize during the winter--usually during December."
Crane: "Last year we used a method of storing Chinese chestnuts which
proved very satisfactory. Two thousand pounds of nuts were stored last
year. Fall planting is good where one can use it but in a lot of areas
it can not be used because of rats robbing the plantings. We have to
store the nuts. The procedure we follow is to harvest every other day.
Nuts are placed in tin cans with friction top lids. The lids should have
one to three holes of 1/16" diameter in them to provide air. Cans are
placed in storage at a temperature of 32 to 40 degrees F."
Stoke: "I keep chestnuts in the cellar in a can with an open top in what
we call limestone sand. Keep wonderfully well. Chestnuts must have air."
Gravatt: "Down south we have a lot of trouble with decay. We take nuts
right from the bur and put them in the soil. They give much better
germination."
Crane: "The Chinese harvest their chestnuts just as soon as the bur
cracks. They do not wait for the nuts to drop from the trees but harvest
the nuts from the trees and store in covered pottery jars. They plant in
the fall of the year. They do not hold nuts for any length of time."
Corsan: "How about charcoal?"
G. Smith: "Charcoal is good to store nuts in. They are shipped from
China that way."
Smith: "Would chestnuts stand carbon bisulphide for getting the weevil
out, or is the hot water treatment better?"
Crane: "Carbon bisulphide treatment is dangerous, it will kill weevils
but it will also kill the nuts so they will not germinate. Unless
precautions are used it may cause an explosion and fire. Methyl bromide
treatment is better."
Stoke: "The hot water treatment is the best. It consists of immersing
the nuts in water at 120 degrees F. for forty minutes."
Hemming: "I have raised about 100,000 seedlings and have never seen
blight on any of my seedlings."
Dr. Smith: "A tree needs usually to be as big as the small end of a
baseball bat before the bark opens enough to let in the blight spores."
Stoke: "Blight begins where there is rough bark which provides lodgment
for the spores. Rough bark and moisture result in blight, hence the
disease usually starts near the ground."
Crane: "The blight problem in the growing of chestnuts has often been
stressed. I think you will have more loss from sunscald and root rot
than you will from blight. Blight is a minor trouble with us. The
Chinese chestnut naturally grows with a low head. It is a mistake to cut
off the low branches on the trees until they attain some size, they can
then be cut off."
Stoke: "Regarding the protection of nut trees against winter sun scald,
I find that if you take ordinary aluminum paint and paint the south and
southwest side of nut trees it will last for two years."
Dr. Smith: "Chestnut trees have blighted for me where the water table
was too high and trees of same origin or better drained ground nearby
did not blight. Blight is often a sign that the tree wants something it
lacks--much like disease in humans."
Results of a Chinese Chestnut Rootstock Experiment
J. W. McKAY[4]
Introduction
The propagation of chestnut species by budding or grafting has been
performed by different workers with varying degrees of success. Many
have found that grafted trees could be produced and grown successfully
but that graft union troubles developed in a certain percentage of the
trees either soon after grafting or a few years later. The variety
"Carr" is known to graft with difficulty in certain localities and to
give a high percentage of poor unions both at the time of grafting and
after a few years of growth. The question of relationship of scion and
stock has been considered by many workers to have an important bearing
on the success of grafting operations but no critical work has been done
to determine this point. Some investigators hold that scions of one
species may be grafted upon stock of another species without harmful
effects. The results of the budding experiment with Chinese chestnut
reported in this paper are the first of a series of tests designed to
contribute needed information about stock-scion relationship in
chestnuts.
[Footnote 4: Associate cytologist, Division of Fruit and Vegetable Crops
and Diseases, Bureau of Plant Industry, Soils, and Agricultural
Engineering, Agricultural Research Administration, U. S. Department of
Agriculture.]
Description and Results