(in the spring) and until August 1st. This encourages root growth and
conserves moisture. Then sow a cover crop of rye, cow peas or soy beans
to take up moisture, slow up growth and prevent the late sappy condition
that is often responsible for winter injury. Leave the cover crop over
winter and turn it under in the spring for humus. Before turning under,
a light application of some kind of manure, along with some
superphosphate and potash, should be sprinkled around each tree. Then
thorough cultivation again until August, and repeat.
"Soil for nut trees should be tested for acidity, nitrogen, phosphate
and potash. It has been determined that most nut trees prefer a pH range
of 6.0 to 8.0; but I have frequently found people planting trees on
soils of 4.0 and 5.0, where nothing but sickly growth could be expected.
"Where it is not possible to work all of the ground between nut trees,
cultivation should begin with a three or four foot circle around each
tree, annually increasing this space with the growth of the branches.
Cultivation, with attention to humus and fertility, are necessary to
proper tree growth and nut production. Sod culture will never do."
Mr. Burgart's method has the advantage not only of guarding the trees
from excessive winter injury but at the same time adds an almost
immediately available source of humus and nutrients to the soil for
spring growth. If followed, it should greatly reduce the number of
reports of winter injury, failure to start, and of weak growth
afterward.
Excessive summer heat is not so great a problem in most portions of the
northern states. The highest expected temperatures range, in our
reports, from 86 deg. to 110 deg.; mostly from 90 deg. to 100 deg.. The highest known
are reported to be all the way from 95 deg. to 120 deg., but mostly from 100 deg. to
110 deg.. A method of guarding against heat damage will be found in a
communication from Mr. H. F. Stoke, of Roanoke, Va., which appears later
in this report.
Drouth and hot, dry winds are more dangerous enemies than either cold or
heat. It is somewhat ominous that, out of eighty-three reports,
forty-two, originating all the way from Maine to Oregon and from Canada
to Tennessee, report the occurrence today of frequent drouths, while
forty report hot, dry winds. Surely the need for tree planting is
immediate and urgent. Mulching, and the protection of recently planted
trees by wrapping their trunks, are preventives of some damage, but can
not stand up forever against the longer and longer periods of drouth now
being reported, during which the water table is gradually being lowered
beyond the reach of tree roots.
The length of the frost-free season has an important bearing upon the
production of nuts after the trees are matured. This is true in the
south as well as in the north. One of the most frequently reported
causes of loss of nut production in southern sections is an early
spring, inducing growth of buds and blossoms, followed by a frost. No
protection seems to have been found against this damage except by use of
heavy smudges. Large orchardists protect themselves, but planters of
small groves rarely do so. This explains the autumn scramble, reported
by many members, in search of early fallen nuts. We should continue our
search for trees which produce nuts of early maturity. Thus far the
search has not been too successful among most species, but some progress
has been made and the future is more encouraging in this respect than it
was a decade or two ago. Some early maturing nuts have been found and
pollen from the trees is being used for cross-pollination with better
known nut producers. In the northern states, dates of the latest spring
frosts range from April 1 to June 1, with the average around May 15. The
earliest fall frosts come from Sept. 5 to Oct. 15, with the average
about Sept. 15 to 20. Where the frosts fall much outside these
limits--too late in the spring or too early in the fall--protective
measures will help but will not always prevent damage.
_Soil Conditions._ There is a slight preponderance of clay soils over
loam among the returns from planters. Loams and sandy loams are tied for
second place. A smaller number report that these top soils lie shallow
over hard-pan or rock. Fewer still report a soil underlaid with sand or
gravel.
By far the best growth for most kinds of nut trees, as well as the best
production of nuts, is to be found where trees are planted in deep loam.
Next come the trees in clay loam; then come trees in sandy loam and in
clay over sand or gravel. Numerous complaints of poor growth come from
members who have trees set in a soil which is shallow over rock or
hard-pan. Some of the hazels and butternuts are reported as able, for a
time at least, to establish themselves in such soils, but their fight
for survival seems precarious and is apparently short-lived. Black
walnuts, particularly, require deep, rich soils into which their long
taproots can easily penetrate. This is one of the few nut tree facts so
definitely established that there can no longer be any doubt about it.
The reports show that the planting of black walnuts in any but good deep
soil should be discouraged. It leads only to disappointment and often to
loss of interest.
A somewhat sandy soil, particularly if loamy, seems adapted to the
planting of chestnuts and to such trees as do well on ground that will
successfully grow peach trees. If such soil is found upon a hillside or
hill top, so much the better. All such soils, of course, require more
attention to fertility maintenance, for they leach out more quickly than
soils with more of a clay constituent.
Do any of the nut tree species prefer an acid to an alkaline soil? This
is a question our questionnaire does not answer. Thirty correspondents
say their trees are set in a lime soil, fourteen in an alkaline soil
(which may or may not, in the commonly accepted usage of that term, have
lime as a source of alkalinity). Sixty-one report an acid soil. Only
eight of this group report the use of lime, two the use of bone meal,
and one of wood ash as acid correctives. Unfortunately, we did not ask
definitely about the reaction of trees to the use or non-use of lime.
Puzzled by this comparative neglect of lime as a corrective on acid
soils, we asked Mr. H. F. Stoke, of Roanoke, Va., a very accurate and
acute observer, who had reported plantings in both kinds of soils, what
his experience had been. Also we asked Miss Mildred Jones, whose
experience with nut trees is second to none, the same question. Their
replies follow:
Mr. Stoke says: "In response to your inquiry, 'What nut trees, if any,
do best in acid soils?' I should reply that the chestnut leads the list,
followed closely by the mockernut hickory.
"Throughout its native habitat the heaviest stands of the native
chestnuts are to be found on acid soils over granitic and sandstone
formations, rather than on limestone ridges. The best stands are on
granite ridges, partly due, no doubt, to the poverty of sandstone soils.
"The mockernut hickory occurs about anywhere on the poor, acid, clay
soils of the south, its vigor depending on fertility. Shagbark does not
occur on the acid (granitic) Blue Ridge mountains, but is found on the
limestone Alleghanies running parallel only a few miles away. I have
never seen a shagbark hickory between Roanoke and the coast, more than
200 miles away, but it occurs freely to within two or three miles on the
west. The difference is not in elevation or rainfall, but in the soil.
"On the other hand, black walnut occurs on both acid and limestone
soils, but seems to prefer the latter. Part of its preference may be due
to the generally greater fertility and better drainage to be found in
limestone soil. Persian walnut, I believe, when on its own roots, is
more or less allergic to acid soil. Wild hazels grow here on both
limestone and granite soils.
"Frankly, I believe the matter of soil acidity, as such, is rather
over-emphasized. There are other factors entering into the problem that
are of as great or greater importance. I doubt if there was actually any
really alkaline soil, in its native state, in the humid region lying
east of the Mississippi River. In the glaciated region lying to the
north, the soil seems to have been more nearly neutral (pH 7). Such was
the case in Iowa and in Minnesota where I homesteaded many years ago.
"Throughout the south the soil averages much more acid, even much
limestone soil being greatly benefitted by liming. North or south, soil
acidity is greatly affected by drainage and by the resulting native
vegetation.
"Peat or muck soils are notably acid; also they are notably deficient in
potash. The addition of wood ashes greatly benefits such soils in two
ways. On the other hand, the addition of wood ashes to a soil already
alkaline might be harmful even though in need of potash.
"In the last several years I have been making some soil experiments that
I may write up when I am sure I know what I am talking about. In
general, I may say I should prefer a soil slightly on the acid side for
any and all tree and farm crops if I had an eye to future fertility.
Lime breaks down vegetable matter and makes its constituent plant foods
quickly available, but prevents a build-up of humus in the soil. The
effect is very pronounced in times of drought, the alkaline soil crops
drying up much more quickly than do those on acid soil. On the other
hand, such soil elements as phosphorus seem to require the lime as a
flux to prevent the phosphates from becoming fixed and unavailable to
crops.
"In regard to peat moss, it is undoubtedly acid, but it is beneficial in
its water-holding properties and in the comparatively slow release of
its nutritive elements. Lime added to the peat will break it down
rapidly and make it more available as a fertilizer, but until the
decomposition reaches a certain point; its effect is to impoverish
rather than to enrich the mixture. This seeming paradox can perhaps best
be explained by some experiments I have been making with sawdust. A
number of plots were prepared and given various treatments, including
mixing one surface-inch of sawdust with the soil, and wheat was sown on
the area.
"Wheat sown on the test plot without any treatment or fertilizer was
normal for the poor clay soil on which the experiments were made. Where
sawdust, only, was added, the wheat came up but sickened and produced no
filled heads. The same was true where lime was added to the sawdust.
Where heavy applications of nitrate of soda were added to the sawdust
treated plots, both with and without lime, the 'sickness' disappeared
and wheat was matured.
"My analysis of this, coupled with experiments in composting, leads to
the following conclusion: During the period of decomposition of the
sawdust (hastened, no doubt, by the lime), the bacteria of decomposition
fed so heavily on the nitrates in the soil that the plants were starved.
When the material had reached the condition of humus, the bacterial
activity decreased to the point where fertility was restored.
"The above analysis accounts for the fact that coarse vegetable
material, injures crops, when plowed under, for the current season.
Fresh succulent material decays so quickly that it becomes almost
immediately available, releasing its constituent plant food.
"With proper conditions of moisture and aeration, sawdust, when mixed
with quickly decaying material like kitchen garbage, can be reduced to
an excellent, usable humus in three summer months. In fact, it is then
better material than if permitted to lie out in the weather for fifteen
years.
"There is another factor I think important in tree growth, especially
where summers are hot, and that is soil temperature.
"For any of our nut trees I should say that an acidity test of pH 6 to 7
would be entirely satisfactory. If the soil is infertile, some form of
humus should be worked in at the time of planting. If much such material
is used, some lime may be added. Better yet, wood ashes and bone meal
will furnish potash, phosphorus, and the lime necessary to correct
acidity and maintain the phosphorus in an available condition. Add to
this, proper drainage and cool soil achieved by, first, cultivation, and
later by heavy mulching, artificial shading, or shrubby undergrowth
extended outside the root area, and your tree should 'go to town.' When
the tree is large enough to shade its own root area it will take care of
its own soil refrigeration. Nature knew what she was about when she
planted trees in forests. Trees require warm heads (sunshine) and cool
feet (shade), just the opposite from us humans."
Mr. Stoke's letter recalls a very ancient Arabian proverb connected with
the date palm. "The date palm tree must have his head in hell and his
feet in water." We are indebted both to Mr. Stoke and to the Arab
scientists for many things.
Miss Mildred Jones' reply, fortunately, goes into other and equally
important phases of the same subject. She says: "Anyone who is going to
lime and fertilize nut trees should take at least a five year period for
his work, using lime and fertilizer each year, and not dump it all in
one year, then wait for results. He should study the return on a five
year basis. One year is too short a term. Weather conditions can upset
a program to the extent that both lime and fertilizer may not have their
effect until the following year. Let those who really want to know, make
graphs of growth in young trees and of nut production from older trees,
in pounds, for five years, as against five of the same years during
which trees similarly situated received no fertilizer or lime.
"I shouldn't be at all surprised if those who state in reports to you
that they have an acid soil, merely have a top acid soil. They may be
growing their trees in basic limestone soils. Walnut trees grow in this
environment very well, because they are found growing wild in woods
where laurel and other types of plants loving an acid condition grow.
This is true here in our county, but these soils are not seriously acid.
They grow good garden crops.
"Ground, or pulverized, limestone is the safest type of lime to apply to
trees or crops, in my estimation. Some of it is ground so fine that it
looks like hydrated lime and is used for medicinal purposes. I am
inclined to think that any reports you received that noted injury from
the use of lime may have been due to the use of burned lime (calcium
oxide) which is caustic when wet. This type of lime may be used in
winter, but during the growing season, or too close to the growing
season, may injure trees. I believe such injury depends entirely upon
weather conditions, but it is a good thing to be on the safe side and
use a lime which will not have the hot reaction that burned lime has.
"Your reports will serve an excellent purpose if they lead to getting a
yearly record by planters on bearing and tree growth of their varieties.
Few people know enough to go into the matter of soils and treatments
intelligently. One can hardly blame them. It is a baffling subject. An
unbalance in one element will lock up another element until one has
quite a time unlocking them again. It seems that a conservative middle
course is about the best to advise."
Upon reflection, it seems likely that if our questionnaire had asked
specifically about the use of lime, many more reports would have been
received of its use.
In response to an inquiry as to how weed competition near young trees is
controlled, the replies are encouraging. Forty-seven practiced mulching;
forty-five, mowing; thirty-four, occasional cultivation; twenty, regular
cultivation, and a few others, slag or cinders around the trees. As is
evident, some used several of the above methods. A few used none and
suffered losses. Their honesty is admired, and their experience,
disappointing as it is, is useful information.
As to fertilizing, forty-three reported the use of manure in some form
as the principal material; twenty-eight used nitrogenous fertilizer;
twenty-one, a complete fertilizer. Other materials were, in order, lime,
compost, bone meal, ammonium sulphate, wood ash, tankage. One used a
mixture of muck and manure and got results in excellent growth where the
use of muck alone produced unsatisfactory growth. Several reported
injury from too much fertilizer or from too late an application. Tree
growth was thus pushed on into late fall; the trees were too sappy to
stand the winter freezes and suffered from winter killing. The same
result was reported from "over-cultivation." In this connection, we
refer back to the letter from Mr. H. P. Burgart, of Michigan, whose
suggestions on cultivation and fertilizing are well worth careful study
and practice by all who have had this trouble. It is possible that some
planters, especially those whose trees are set on hillsides, where
erosion is a robber of fertility, would modify Mr. Burgart's practice of
turning under the green crop in the spring. They might prefer, as indeed
might others who would like to see their green manure nearer the top of
the soil, to disk in the green crop rather than bury it deeply with
mouldboard plows. They would of course follow it up with repeated
diskings until the time came for sowing another cover crop. This is,
however, entirely in line with Mr. Burgart's recommendations.
Pursuing this subject to its conclusion, we next asked: "_When young
trees failed to grow with you, what percentage of these failures was due
to_ ..." (various causes enumerated below)? The question was
misunderstood. Many evidently gave percentages of all trees planted.
Others, correctly, gave percentages merely of the trees which failed to
grow. As nearly as could be arrived at, about 30 percent of losses were
among trees that failed even to start; 40 percent failed from weak
growth the first year or two; 10 percent from failure to maintain later
growth; 16 percent were winter killed, and 3 or 4 percent died from
rodent or similar (mole, gopher, deer, bear) injury. It is evident that
by far the greatest losses were suffered within the first two years--not
less than seventy percent. Probably more. It would seem that two years
of intensive care should not be too burdensome a stint for a reward
which lasts a lifetime.
Rodent and similar injuries were no doubt kept low because of extra
protective care. Hardware cloth (galvanized wire 1/4" mesh, 24" high,
preferred) around each tree proved the most common and effective
preventive. Following this, in order of use, were: wrapping the trunks
(including wrappings of tar paper); mounding with earth or ashes; poison
bait, dogs and cats, clean cultivation; resinous paint; spray (with
Purdue formula mentioned); and, finally, hogs, against mice.
Anti-rodent treatments which proved injurious to trees were reported to
be; tar paper wrappings; coal tar washes; close-set creosoted posts; oil
sprays; "any paint"; any chemical to smear on trunks; rooting cement.
For those who are located in regions where deer are a source of injury,
Mr. J. U. Gellatly, of West Bank, B. C., reports the successful use of
an old and heroic Russian formula. Spray or paint all branches with
manure water, using hog or human offal. Deer will stay away. Naturally.
Next come answers to some personal questions as to experiences from
which the reader may glean a wide variety of suggestions. The first of
these questions is:
"_What is your ONE greatest source of success?_" The answers seem to
show many royal roads, each of which was the one road for someone. The
answers: Mulching young trees; watering care; planting seeds; planting
one-year seedlings; wrapping-with paper; 50% moist peat mixed with earth
in transplanting; manure; sod in bottom of planting hole and use of
nitrogen later; setting trees at bottom of slopes; clean cultivation
until August then sowing rye, soy beans or cow peas as cover crops to
turn under in spring; topworking hickories; grafting in cool, moist
spring weather; pigs in orchard; chickens in orchard; planting
12-14-foot trees severely cut back, burlap wrapped, heavily mulched.
It seems a pity that limitations of space do not permit the telling of
the various stories connected with the above glimpses of successful
solutions. Each represents a little or a big success story connected
with an individual problem. It is sufficient, perhaps, to know that
someone somewhere found that each was the answer to his own
difficulties.
The next question brings out the reverse side of the planters' work:
"_What is your chief source of failure?_" The answer most often given
was the honest one, lack of attention. We can all convict ourselves
here, either involuntarily or otherwise. Especially during this period
of warfare, when so many have been taken away from their plantings and
have been unable to get help, there is no question but that our trees
have suffered. The next in frequency is "unsuitable soil." Following
this come: lack of water; poor planting; planting too big a tree; spring
planting of nut trees; buying 5 to 7 year-old trees; climate;
transplanting failures; grafting; grafting in dry, hot, springs;
top-working old trees; stink bugs on filberts (nuts); lack of drainage;
forcing with nitrogenous fertilizer; fertilizing young trees too much;
birds breaking off top growth. It had been the intention to confine this
question to young trees, but it was not so phrased, so we shall let the
answers stand as they are. It is a bit ironical that some found their
chief source of failure exactly where others had made their best
success. The explanation must lie in differences in technique, in soil
or in some other local condition. Skill, knowledge, and persistence must
always play a great part in any success.
We next asked, "_What have been your chief difficulties with
established, bearing trees?_" The difficulties here shift from matters
of soil, rodent protection and the like to other types; caterpillars,
neglect, winter injury, limited crops, failure of nuts to fill,
disappointing quality of nuts, bag and tent worms, blight, "blight" due
to drought, too early leaf fall, insects in early spring, trees drowned
out in flooded bottom lands. It is probable that this last disaster
happened to younger trees.
As to the species of trees chiefly damaged by these causes, black walnut
comes first (possibly because more of these trees have been planted),
then hickories, Persian walnuts, chestnuts (blight), heartnuts, pecans,
filberts, butternuts, and finally butternuts in the south areas from
fungus troubles.
Trees reported to have been least damaged were, first, butternuts, then
hazels and filberts, black walnuts, hickories, Manchurian walnuts, Jap.
walnuts, heartnuts, chestnuts, pecans, Persian walnuts.
In response to the specific question, "_What insects damaged the
trees?_", we found that walnut caterpillars were more common than any
others, followed closely by web or "tent" worms. The Japanese beetle is
a close second and is broadening its entrenched positions steadily.
Others are flat-headed apple borers, lace-wing fly, aphis, leaf hoppers.
To this list two reporters added sapsuckers among the insects. These
birds would almost girdle some of the branches with punctures.
Insect damage was reported as serious by eight reporters, as slight or
occasional by six, and of yearly occurrence by nearly all. Others
reported damage as serious if not controlled.