So far as we know, the hickories, belonging to the Juglandaceae, are
indigenous to the North American continent only. Representatives of the
group occur naturally from southern Canada to the central latitude of
Mexico, in a curved band upon the map, which would be bounded upon the
east by the Atlantic Ocean and the Gulf of Mexico, and on the west
roughly by the Missouri River, until that river bends east from the
eastern boundary of Kansas. From the angle of that bend the hickory runs
approximately southwest into Mexico.
The exact number of species has not been determined as yet, because of
the open question of specific or varietal differences in some members of
the family. Sargent's classification at present includes eleven species:
Hicoria pecan, H. Texana, H. minima, H. myristicaeformis, H. aquatica,
H. ovata, H. Carolinae-septentrionalis, H. laciniosa, H. alba. H.
glabra, and H. villosa. To this list may be added H. Mexicana (Palmer),
which so far seems to have been found only in the high mountains of
Alvarez, near San Louis Potosi in Mexico; and H. Buckleyi from Texas,
which was described once by Durand, and since that time overlooked by
writers, excepting by Mrs. M. J. Young in 1873, who included the species
in her "Lessons in Botany." Professor Sargent tells me that the Buckley
hickory will be included in the next edition of Sargent's "Manual of the
Trees of North America." This brings the number of species up to
thirteen. In addition we have well marked varieties: H. glabra odorata,
H. glabra pallida, and H. glabra microcarpa, making sixteen well defined
hickories that have been described.
Nuts of all of these hickories are in the collection of "Edible Nuts of
the World" at Cornell University, with the exception of nuts of the
varieties H. glabra odorata and H. glabra pallida.
In addition to the sixteen described varieties and species of hickories
in America, we have an endless variety of hybrid forms, because
cross-pollenization seems to take place readily between hickories of
synchronous flowering time.
Five of the hickories: H. pecan, H. Texana, H. minima, H.
myristicaeformis, and H. aquatica belong to the open-bud group, while
the rest belong to the scale-bud group. The winter buds of the open-bud
group resemble the winter buds of the walnuts in a general way, and in
artificial hybridization experiments I seem to note a close relationship
between the open-bud hickories and the walnuts.
There is no more promising work for the horticulturist than crossing
hickories with walnuts, and crossing hickories with each other. Five
hundred years from now we shall probably find extensive orchards of such
hybrids occupying thousands of acres of land which is now practically
worthless. The hickories are to furnish a substantial part of the food
supply of the world in the years to come. At the present time wild
hickories held most highly in esteem are: H. pecan, H. ovata, H.
Carolinae-septentrionalis, and H. laciniosa. Several other kinds have
edible kernels, sometimes of excellent character, but not readily
obtained except by boys and squirrels, whose time is not valuable. In
this group we have H. alba, H. glabra, H. villosa, H. glabra pallida, H.
glabra odorata, H. glabra microcarpa, H. Mexicana, H. Buckleyi, and H.
myristicaeformis. In another group of hickories with temptingly thin
shells and plump kernels, we have a bitter or astringent pellicle of the
kernel. This group contains H. Texana, H. minima, and H. aquatica.
Sometimes in the bitter group we find individual trees with edible nuts,
and it is not unlikely that some of them represent hybrids in which the
bitter and astringent qualities have been recessive.
Among the desirable species of wild hickories there is much variation in
character, and selection of trees for propagation is in its infancy. One
reason for this has been the difficulty of transplanting hickories.
Another reason is the fact that hickories do not come true to parent
type from seed. A third reason is the length of time required for
seedling hickories to come into bearing.
Concerning the first reason, the enormous taproot of young hickories
requires so much pabulum for maintenance that when the trees are
transplanted, with destruction of root-hairs along with the feeding
roots, transplanted stocks may remain a year or two years in the ground
before they are ready to send out buds from the top. On this account,
the Stringfellow method has in my locality proven of value. This
consists in extreme cutting back of root and top, leaving little more
than a short club for transplantation. The short club does not require
much pabulum for maintenance, and new feeding roots with their
root-hairs get the club under way quickly, because there is little
useless load for them to carry. The Stringfellow method further includes
the idea that stock should be planted in very hard ground, and seems to
be practicable with the hickories. The root-hairs which take up
nourishment from the soil find it difficult to carry on osmosis in loose
soil. The close contact obtained by forcing a way through compact soil
facilitates feeding. On this account, autumn is perhaps a better time
for transplantation of hickories, in the northern latitudes, at least.
Callus forms over the ends of cut roots at all times when the ground is
not frozen, and the more complete the callus formation the more readily
are feeding roots sent out.
One of the main obstacles to propagation of hickories has depended upon
the fact that nuts did not come true to parent type from seed. This is
overcome by budding or grafting, and we can now multiply the progeny
from any one desirable plant indefinitely. In the South grafting is
nearly as successful as budding, but in the North budding seems to be
the better method for propagation. The chief difficulty in grafting or
budding the hickories is due to slow formation of callus and of
granulation processes which carry on repair of wounds.
The propagation of trees from a desirable individual plant can be
accomplished also by transplanting roots. A hickory root dug from the
ground, divested of small rootlets, cut into segments a foot or more in
length, and set perpendicularly in sand with half an inch protruding,
will throw out shoots from adventitious buds. In my experimental work
with hickory roots, in covered jars, surrounded by wet moss, but with
the entire root reached by light, adventitious buds have started along
the entire length of the root, and we may find this an economical way
for root propagation, dividing up sprouting roots into small segments.
The chief objection to this method of propagation as compared with
budding is the length of time required for seedling trees to come into
bearing, propagation from roots probably requiring the same length of
time as propagation from seed, whereas by budding or grafting the
bearing period begins very much earlier. Forty-six years ago Mr. J. W.
Kerr of Denton, Maryland, planted three pecks of large shagbark hickory
nuts, but of the progeny only about twenty were satisfactory, most of
the trees bearing inferior nuts. These trees required from thirteen to
eighteen years to come into bearing, and young trees that Mr. Kerr
purchased from nurseries and planted were twenty-five years old before
they began to bear. Others who have planted shagbark hickories and
pecans state that nearly twenty years are required for the trees to come
into bearing on an average. When budded or grafted the pecan sometimes
comes into bearing in two years, and frequently in four years. We may
anticipate that other hickories will act analogously.
The hickories prefer rich, well drained soil for best development of
nuts, and an abundance of moisture, provided the land is well drained.
Many of the hickories, however, are so adaptable to various soils that
they often thrive in lands that are sandy, and dry, and almost barren.
In the latter case, they have to maintain an enormous root system for
feeding purposes, and this is detrimental to good bearing qualities. The
mocker-nut, pignut, and hairy hickory, perhaps adapt themselves best to
sandy soils. This feature may make them valuable species for planting
when one has no other soil, because the stocks can be used for grafting
better kinds.
While the hickories prefer neutral or alkaline soil, most of them will
grow fairly well even in acid glacial tills. Their preference, however,
for neutral or alkaline soils would suggest the use of a good deal of
lime in acid soils, when hickories are to be grown in orchard form.
All of the trees in the hickory group are intolerant of shade and of
competition with other trees. The more sunlight they can have the
better. Most of us are familiar with the hickory tree standing alone in
the cultivated field, which bears a heavy annual crop, when the
neighbors at the edge of the forest bear sparingly. Hickories in forest
growth put their energies into the formation of wood chiefly, and in the
struggle for food and light devote very little energy to fruiting.
The best method for cultivation of hickories has been worked out only
with the pecan up to the present time. With this species, it has been
determined that clean cultivation with plenty of fertilization gives
best results, as with apples. It is probable that Stringfellow's sod
culture method will come next in order, and will perhaps be most
generally used by nut orchardists, because it is less expensive and
requires less labor. The sod culture method includes the idea of cutting
all grass and weeds beneath the trees, in order to take away
competition, allowing these vegetable substances to decompose beneath
the trees and furnish food. There is no objection to adding artificial
fertilizer, or a still greater amount of vegetable matter.
The enemies of the hickories are not many in the forest, where the
balance of nature is maintained, but when man disturbs the balance of
nature by planting hickories in large numbers in orchard form certain
enemies increase, and must be met by our resources. Fungous and
bacterial enemies are beginning to menace some varieties of the pecan in
the South, and both in the North and in the South certain insect enemies
are becoming important in relation to all valuable hickories.
The bark boring beetle (Scolytus) has been reported as destructive to
hickories in some sections, the trees dying as a result of depredations
of the larvae of this beetle.
I find a large borer at work on some of my hickories, but have not as
yet determined its species. It may be the painted hickory borer
(Cylene), or the locust borer. It makes a hole as large as a small lead
pencil, directly into the trunk or limbs, and excavates long tunnels
into the heart wood. The painted hickory borer is supposed to occur
chiefly on dead and dying hickories, but the borer of which I speak is
found in the vigorous young hickories in the vicinity of my locusts,
which are riddled with locust borers.
In some localities involucre borers make tunnels between the nut and the
involucre, interfering with the development of the kernel.
The hickory twig girdler (Oncideres) is abundant in some localities, but
not as yet very destructive.
Hickory nut weevils destroy many nuts in some localities, and their
colonies increase about individual trees markedly. In such cases, it is
important to collect the entire crop each year from a given tree, taking
pains to destroy all nuts which contain weevil larvae. These may be
selected in a general way by dumping the freshly gathered nuts into a
tub of water. Nuts containing weevil larvae will float for the most
part, and in order to make sure of the destruction of larvae in the
remaining nuts they may be placed in a closed receptacle, and carbon
bisulphide poured over them.
One of the bud worms is sometimes very destructive to individual hickory
trees which have developed colonies, the larvae destroying the axillary
buds, and burrowing into the base of the petioles of leaves.
A new enemy which I found this year for the first time is the
Conotrachelus juglandis. This beetle ordinarily lays its eggs in the
involucre of the butternut. With the introduction of exotic walnuts, the
beetle has changed its habits, and lays its eggs in the herbaceous
shoots of walnuts and hickories. The larvae tunnel into the center of a
shoot, and destroy it, or seriously interfere with its nutrition.
Among the enemies of the hickory we must not forget the common field
mouse, and the pine mouse, which burrow beneath the surface of the
ground, and in winter feed freely upon the bark of the roots of the
hickories. They have destroyed many thousands of young hickories of
various kinds in my nursery, and in digging up roots of old hickories
for experimental root grafting I find that mice have been living freely
for years upon the bark of some roots.
Aside from the facts which have been grouped together in this paper,
certain notes may be of interest, as introducing questions for
speculation.
Are we likely to find more species among the hickories than the ones
already described? If so well described a species as the H. Buckleyi has
almost escaped observation, and if H. Mexicana is confined, as it seems
to be, to a very limited area, and if most of the hickories grow in
regions where few botanists are at work, it seems to me probable that
several species remain as yet undiscovered. These are likely to be
species which lack means of defence, and which are restricted to certain
small areas. If we make a parallel with other observations of recent
discoveries, one thinks, for instance, in Ichthyology of the Marston's
trout, the Sunapee sabling, Ausable greyling, and the Kern River trout,
confined almost to a certain stream or lake, and remaining undiscovered
for years by naturalists, although familiar to thousands of local
fishermen.
Sometimes there is a very apparent reason for the check to distribution
of a species. The men whom I employed to go into the mountains of
Alvarez for the Mexican hickory tell me that the trees are so loaded
down with mistletoe that they rarely bear a crop, and there are few nuts
with well developed kernels to be found.
Distribution of a powerful species of hickory, like the pecan, seems to
be limited in the North by incomplete development of the pistillate
flowers. These are borne on the ends of the herbaceous shoots of the
year, and the pecan has such a long growing season that in the North the
pistillate buds, which are last developed, are exposed to winter
killing. Southern limitation of hickories which have a very short
growing period, like the shagbark, may be due to the fact that after a
period of summer rest, new growth begins in the autumn rains, and this
new growth may not lignify for winter rest.
By artificial selection we can extend the range of all hickories far
beyond their indigenous range, which is limited by natural checks.
Extension of range, adaptation to various soils, and changes in the
character of the nut are likely to occur from grafting hickories upon
different stocks of the family. Thus we can graft a shagbark, which does
not thrive in poor sandy soil, upon the mocker-nut, which does grow in
such soils. Some varieties of the species may grow freely far out of
their natural range if they are simply transplanted. For instance, the
Stuart pecan, which comes from the very shores of the Gulf of Mexico, is
one of the hardiest pecans at the latitude of New York. I don't know
about its northern fruiting as yet.
If the Satsuma orange grafted upon trifoliate orange stock gives a
heavy, well flavored fruit, while the same variety grafted upon sweet
orange stock gives a spongy fruit of little value, we may assume that
similar changes in character of fruit will follow nut grafting. Perhaps
the astringent feature of the pecan nut will be found to disappear when
the pecan has been grafted upon certain other hickories. Sometimes
undesirable results are obtained from such grafting; for instance, the
pecan grafted upon water hickory stock has been found to grow freely for
four or five years, and then to die back unaccountably.
Stocks of rapidly growing hickories, like the pecan and the bitternut,
may serve to shorten the bearing time of slowly growing species, like
the shagbark, when scions of the latter are grafted upon such stocks. At
the present time I have shagbark grafted upon stocks of the pecan,
shagbark, bitternut, mocker-nut, and pignut, but these are all young,
and I cannot at the present time discern much difference in effect of
stock upon scion.
In cross pollenization of hickories, I have not as yet discovered the
best way to prevent the development of aphides and of other insects
under the protection of the paper bags (which cover the pistillate
flowers) sometimes to the point of destruction of flowers before nuts
are started. It is probable that sprinkling the leaves with Persian
insect powder, and leaving a little insect powder in the bag, will
settle the question.
I have not as yet learned how to prevent squirrels from getting at
hybridized nuts while they are still upon the tree. Squirrels cut
through mosquito netting which is tied about nuts to prevent them from
falling to the ground, and if wire gauze is used, they cut off the
branch, allowing gauze and all to fall to the ground, and then manage to
get the nut out of the gauze. The red squirrel particularly is a pest in
this regard, and will even cut off the tape which is tied about the
branches for marking purposes, for no apparent reason aside from pure
mischievousness.
Nuts which are to be planted must be kept away not only from the
squirrels, but from rats and mice. One of my farmhouses got the
reputation of being haunted because of mysterious noises made by rats in
rattling hybrid nuts worth a dollar apiece about between the partitions.
The best way that I have found for keeping nuts for sprouting purposes
is to have a number of large wire cages made. These are set in the
ground, nuts are stratified in sand within these cages, and allowed to
remain exposed to the elements during the winter.
It is probable that some of the hickories will be grown in forest form
in future because of the increased value of the wood of the species. For
growing hickories in forest form, it is probable that they should be set
not more than six or eight feet apart at the outset. At ten years of age
the first thinning will give a valuable lot of hoop poles. The second
thinning will give turning stock. The third thinning will give wood for
a large variety of purposes. I know of no tree which promises to return
a revenue more quickly when planted in forest form than hickories like
the shagbark and the shellbark, mocker-nut and pignut. These trees will
not be expected to bear nuts, because in the struggle for food and light
their energies will be directed toward making trunks.
Hickories are undoubtedly to be used for decorative purposes in parks
and streets by future generations. The stately pecan, the sturdy
shagbark, can be made to replace, South and North, the millions of
useless poplars, willows, and other bunches of leaves, which please the
eye but render no valuable annual or final returns. The chief reason why
this has not been done is because people have not thought about it.
President Morris: This paper is not to be considered with the respect
that is ordinarily due to a presidential address, but is open for
discussion, and I would like to have any of my theories disproven.
Professor Craig: Doctor Morris has covered a very extensive field in his
presidential address, and has raised so many interesting questions that
I imagine the difficulty with you is to know just where to begin.
Personally, and because I am not as thoroughly aware of the field of
Doctor Morris' hybridization work as I ought to be, I should like to ask
him what combinations of the hickories he has effected thus far. The
field of hybridizing nuts is an exceedingly interesting one, and Doctor
Morris has been the foremost worker in it. I am sure it would be
interesting to you, as it is to myself, to know briefly what ground he
has covered in the extensive range of his experiments.
President Morris: In answering that question, I am speaking from memory
and may not speak correctly. I have made crosses back and forth between
shagbark, bitternut, mocker-nut, pignut, and pecan. In the crosses I
made, using pecans, pollen was received from the South and put upon the
others. The number of crosses that are fertile I cannot state as yet,
because I have not had experience enough in protecting these nuts, and
many of the hybrid nuts were lost. Squirrels and mice destroyed the
labor of three of my men and myself during one season. I have secured
fertile hybrids between the pecan and the bitternut and between the
pecan and the shagbark. If I remember correctly, those are the only
fertile hybrids I have between hickories at the present time. In regard
to crossing hickories and walnuts, I have crossed back and forth several
of the walnuts, our black walnut, our butternut, the Siebold walnut,
with the pecan, and with the bitternut, and have fertile hybrids. These
are open bud hickories, and the open bud hickories seem to cross
pollenize freely with the walnuts back and forth, while the scale bud
hickories do not accept pollen readily from the walnuts. I would rather
perhaps not make a report to this effect for publication at the present
time, for two reasons. In the first place, I am speaking from memory; in
the second place, rats, mice, squirrels, small boys, visitors, and high
winds have made such inroads upon my specimens, and upon my work, that
it is not quite time to report. I am merely speaking offhand in a
general way, stating that the hickories, open bud and scale bud, both
seem to cross rather freely back and forth. Open bud hickories and the
walnuts seem to cross rather freely back and forth, while the walnuts
and the scale bud hickories apparently do not cross so readily back and
forth.
Professor Craig: In growing your hickories from root cuttings, have you
had any trouble from excessive sprouting?
President Morris: Anywhere from one to eight sprouts will start from
adventitious buds at the circle near the ground, and then I break all
these off but one, letting that one grow.
Mr. Wilcox (Pennsylvania): How do you prepare your stocks for budding
and grafting, in pots?
President Morris: I have tried practically every method that has ever
been described, and the only successful method that I have now has been
topworking vigorous sprouts of one year's growth. That is, I would cut
off the tops of the trees now. Next spring those tops send out very
vigorous sprouts. I bud those early in August or the latter part of
July, or else in the following spring, sometimes, we graft them; and in
grafting, it is quite important to cut longitudinally at one side of the
stock, and go clear to the cambium layer. That gives the flexible slice
on one side, and adapts itself to the tying.
Mr. Wilcox: Have you prepared any stocks in pots at all?
President Morris: Yes. I personally have to leave these to others. I
tell my men to do it, but it is rather new work for them, and I give
them so much to do that things are apt to be neglected; and just a
moment of neglect at the wrong time will wipe out a whole year's work. I
have not cared very much at the present time for root grafting in pots.
I have lost a great proportion of the grafts, and it does not at the
present time seem desirable; but I believe if that is done in hot houses
with the ground warmed from the bottom, it is very apt to succeed. Give
them plenty of time for granulating. They granulate very, very slowly.
Mr. Wilcox: What kind of pots do you use?
President Morris: Some Professor Sargent showed me, long, made for the
purpose.
Mr. Collins (Pennsylvania): You spoke of the hairy hickory. What hickory
is that?
President Morris: Hicoria villosa, that you find from Carolina
southward.
Mr. Littlepage: You spoke of the Stuart as being the most hardy pecan in
the latitude of New York. I presume you meant of the southern pecans?
President Morris: It seems to be one of the hardiest anyway. Even
Virginia forms don't stand it through the winter as well as the Stuart.
Mine are not fruiting as yet.
Mr. Littlepage: What varieties have you there?
President Morris: Appomattox and Mantura are northern ones I have.
Mr. Littlepage: Have you none of the Indiana varieties?
President Morris: Yes, I have the Indiana varieties on northern stocks,
but those have only gone through one winter. They went through all
right. I would say that the Stuart is quite as hardy as those.
Mr. Littlepage: I have observed the Stuart in Indiana. A friend of mine
has a small orchard of several varieties of pecans. I notice some places
where the Stuart has lived six or seven years, and then some
particularly hard freeze has frozen it back. I have a letter from Mr.
Jones in Louisiana, in which he says they had a recent freeze, and
every variety of pecan he had there had suffered, except the Stuart. I
don't recall whether he mentioned the Moneymaker in a previous letter or
not, but he did mention the Russell and some other varieties.
President Morris: We have a number of pecan trees about New York that
have been grown on private estates. Pecans have been planted in
Connecticut and Massachusetts. You run across seedling trees here and
there, and a good many of them are perfectly hardy. They are very apt to
be infertile. The staminate flowers are apt to be destroyed because they
mature so late, and they may not carry any nuts. Pollination is
imperfect as a rule, and nuts may not fill.
Mr. Reed (Washington, D. C.): But trees of Stuart are in bearing?
President Morris: I don't know about bearing. Three years they have
stood a temperature of twenty below zero, so that is a pretty good test.
Mr. Reed: You haven't seen any nuts yet?
President Morris: No, I haven't seen any nuts; but they mature their
wood, and if they mature their wood, they are likely to mature staminate
and pistillate flowers.
Mr. Littlepage: While it is true they may mature staminate and
pistillate blossoms, the question arises whether or not the growing
season is going to be long enough at the end to mature the nuts. I
notice in going through wild groves in Indiana, once in a while you have
a tree which never matures any nuts, though it has bountiful crops. The
frost gets them.
Professor Craig: There is evidently a lack of summer heat to ripen
fruit. Before we get quite away from this subject, I would like to ask
Mr. Roper if he has noticed any striking differences in the hardiness of
Stuart and other northern forms of the pecan in his particular locality.
Does Stuart maintain its reputation for hardiness in his locality? We
are interested in that question from the northern standpoint.
Mr. Roper (Virginia): I think it does, but that is discussed in a paper
which I shall read some time here in the meeting. Both the Stuart and
Moneymaker have done better with us than any other of the southern
varieties when they are budded on hardy stocks. The grafted trees do not
do well with us.
President Morris: Professor Lake, will you speak on any of these
points?
Professor Lake: I am learning much and prefer to continue a learner. I
shouldn't know anything about this crossing, except in the case of the
Juglans regia and the oaks of California. That is one case that was
not mentioned. We have a remarkable hybrid between the native oaks and
the Persian walnut. It is remarkable in many ways. It has foliage that
is perhaps half way between the oak and the walnut, and the nut on the
surface looks like a small walnut, and on the inside it is between a
walnut and an acorn. I had an opportunity to sample the flesh, but it is
not edible yet. They are interested in the work very much, especially at
Chico and the Southern California Station.
President Morris: It is said to be a cross between the live oak and the
walnut. It seems absolutely impossible, but I have seen the nuts, and a
photograph of the tree.
Mr. Reed: We haven't devoted a great deal of attention to the
hybridization of nuts in our Department work. There is one thing that
occurred to me, as I sat here, merely of passing interest. A gentleman
in Mississippi sent a specimen of foliage, together with berries, from
what he said was a hybrid between the pecan and the China berry; and he
had the evidence, because the parent pecan tree stood right there, and
the China berry was the other parent tree! He wanted world wide
attention called to that. They were taken to the botanist, and he
recognized them as one of the ordinary soap berries. There was a similar
case this fall. A gentleman in Texas exhibited some nuts at the State
Fair at Dallas that he said were a hybrid between the mocker-nut, the
common hickory there in Texas, and the pecan. He said that the parent
trees stood near one another and that the pecan blossomed some years
about the same time that the hickory did, and in those years the hickory
nut was long, and in other years it was short. Somebody sent one of the
nuts to Mr. Taylor, Assistant Chief of the Bureau of Plant Industry. He
sent the nut on to me, and I looked it up. I struck Texas on one of
those cold wave days, and drove five miles out and back in a Texas
livery rig, and found an ordinary hickory that bore nuts just a little
different from others. That is one way the Department is called upon to
ferret these things out.
Mr. Littlepage: I would like to ask Mr. Reed what information he has as
to the success of pecans bearing when grafted or budded on other
varieties of hickory? I say that because I know from traveling around
through the country that there is a widespread impression that it is
possible to have very extensive pecan orchards throughout the North by
topworking the wild hickory. I have had some little experience along
that line, but I don't know what the facts are; and Mr. Reed has made an
extensive trip recently for the Department of Agriculture, collecting
data in reference to the pecan.
Mr. Reed: The present situation, so far as we have been able to gather
the information, is just this. The pecan has been grafted on a good many
species of hickory, all the way from Virginia south to Florida, and west
to Texas; but rarely ever can we find an instance in which they have
produced satisfactorily after they have come to a bearing stage. We find
that they unite readily ordinarily, and grow rapidly; but the pecan
eventually proves to be a more rapid grower than the hickory, and when
it catches up and is the same diameter, then the pecan growth is slower,
and while they bear a little the first few years, later on they are not
productive. I don't wish to say that is final, but it has been the
experience so far. You will find most enthusiastic advocates of pecan on
hickory where it hasn't been tried for any length of time. The men who
try it find it unites readily and makes this quick growth, and think the
question is solved. But aside from a few instances in Texas, I don't
find very encouraging reports. It may be due largely to the fact that
the right varieties of pecan haven't been used. We know that in the
early history of pecan culture the Rome and Centennial and some others
that are light bearers were used; and then the pecan on hickory has been
looked at as so much saved, and they haven't been given much attention.
It is still very much a matter of doubt, but is not in a very favorable
light at present.
Professor Craig: I would like to ask Mr. Reed if he has looked over Mr.
Ramsey's work recently at Austin, Texas.
Mr. Reed: I was at Mr. Ramsey's last year, and I don't recall that that
matter came up at all.
Professor Craig: Didn't you see his plantation of top worked hickories?
Mr. Reed: I didn't know he had topworked hickories. He has topworked
pecans. Professor Kyle of the Station in Texas has recently issued a
bulletin on that very thing, and he cites a number of cases in which he
concludes that there will be a favorable outcome; but for some reason,
in the instances which he cites, the trees haven't borne very much. They
attribute it this season in one instance to the fact that they had a
storm at pollinating time, and last year some other accident happened
that prevented them from maturing after a quantity of nuts had set.
Mr. Littlepage: I mention this at this time because I want to get Mr.
Reed's testimony in the record, because I think that every prospective
nut grower must go through this stage. A year ago I undertook on my farm
in Indiana to bud the pecan into other varieties of hickory—I have a
great many wild hickories growing all over my farm,—shagbark,
shellbark, and different varieties of those even. So I went to work and
budded perhaps one hundred of those trees, and for a while it seemed
that there was going to be a great degree of success. I budded them all
upon the limbs where the bark was thinner, and tied the bud in with
waxed cloth very tightly; and by absorption the majority of the buds
lived a week or ten days. After that, there was perhaps a third of them
alive. For the next two weeks, we could find an occasional bud that
remained green, and then the number became so very small that I gave up
the idea that any would live. But this spring I found a few of these had
started to grow, but I had tied them so very tightly that in some
instances where there had been a growth of an inch or two, the bud part
had been cut in two. Then I undertook it on a much smaller scale. I cut
back eight or ten small hickory trees three to four inches in diameter,
let them throw up water sprouts, and budded into these. The bud wood I
used stuck very tight, and I examined the buds in November, and there
were quite a number alive of the Greenriver and Huntington varieties of
pecan. Whether they will grow finally remains to be seen.
(A discussion then occurred as to holding the afternoon session and
it was decided to continue the business during the afternoon,
instead of visiting the Campus.)
President Morris: I would like to comment on one point made by Mr.
Littlepage. He has given us perhaps the reason why pecans die back when
grafted upon other stocks. Mr. Reed, that is an extremely important
point. He has shown that the pecan grows so much more rapidly than other
hickories that when it has arrived at a proportion to be supported by
the root of the other hickory, it then ceases bearing because all the
energy is required for maintaining this new pecan top that tries to grow
faster than the hickory, if that is my understanding of this point.
May we not graft freely back and forth hickories of kinds which have
about the same rate of growth, and may we not graft other kinds of
hickories upon pecan stock, for we don't care how much nourishment is
given to a fine young shagbark?
Mr. Littlepage: That is a fine point.
President Morris: I am very glad Mr. Reed brought up that point. It is
going to save thousands of dollars if it is a fact recognized in time,
because many would go to putting pecans upon other hickories. We may
learn that certain kinds of hickories can be grafted to advantage upon
other stock, however.
Mr. Reed: There is another point right there I would like to have your
views on, and that is, the smaller the hickory is at the time the pecan
is grafted on it, the greater will be the influence of the pecan on the
hickory.
President Morris: It can drag the stock along perhaps. It has been
proved, I think, that a graft has a certain influence upon the stock,
and in some cases can drag it along willy nilly to a certain extent. The
root and the top get to balance each other fairly well if the root is
very small at the time the graft is put on. Most of the trees that have
been topworked to pecan have been various kinds of large hickories.
Perhaps if you were to take a shagbark hickory one to two years of age
and graft it, the pecan top would dominate or control that root, no
matter whether it wanted to grow or not.
Mr. Reed: The claim is sometimes made that if the pecan is grafted on
other hickory young enough, it will transform the hickory completely. It
will make a sufficient root system to feed the pecan as well as the
pecan root would. But I have never seen that demonstrated.
President Morris: That is speculative. It is a very valuable point, one
of the sort of points that would naturally be brought out at a meeting
of this kind.
Mr. Reed: Have you seen that with other fruits, Professor Craig?
Professor Craig: Yes. Each variety of apple produces its own kind of
roots without reference to the seedling stock. That is to say the scion
overrules the root in budding or grafting upon one or two year old
seedlings.
President Morris: A parallel that comes to mind now is the grafting of
Burbank's Royal walnut upon ordinary walnut stock. When that was done,
his Royal walnut was said to drag the other walnut along.
Professor Craig: I think it is a very valuable suggestion. I am not sure
I will go as far as the President has gone; but I think it is
exceedingly suggestive, and worthy of careful consideration.
Mr. Rush (Pennsylvania): I find the same experience in some instances,
that the graft outgrows the stocks. That is a peculiar instance of the
work of improper unions. Eventually the stock pushes up and forms a
perfect union in growth, with the Persian walnut. This is particularly
applicable to pecan and hickory. I suppose Mr. Reed will bear me out in
that, with regard to English walnut and black walnut.
Mr. Reed: Oh, yes.
President Morris: You occasionally see a variety of apple grafted on
another in which the graft part gives the tree a sort of slipshod
appearance. How about the bearing in that kind of a tree?
Professor Craig: They usually bear heavily where the food supply is
restricted.
Mr. Reed: That would make our pecans bear more heavily on hickory stock
than on their own.
Professor Craig: As a matter of theory, they ought to. The bearing
ought to be increased, because it is a system of girdling, or brings
about the same effect,—in other words it restricts the return flow of
the elaborated food. The food is checked at the point of union. Another
parallel is in the case of Prunus domestica, the European plum, when
worked on Prunus Americana, the American plum. In that case, the top
always outgrows the stock, and in ten years it presents a very curious
appearance. It presents the appearance of a very top-heavy head on a
very spindling stem. The bearing is usually encouraged, but the fruit is
usually small. The amount of fruit measured by numbers is increased, but
the amount of fruit measured by the size of individual specimens is
decreased.
Mr. Collins: Isn't the size of the fruit increased in the case of
apples?
Professor Craig: By topworking, usually, it is, but that doesn't
contemplate such an extreme case as that. It means when the union is
reasonably uniform, when there is a reasonable affinity between stock
and scion. But in extreme cases we get the opposite result. Reproduction
is encouraged, but size of fruit is checked.
President Morris: I would like to hear from Mr. Rush or Mr. Pomeroy in
connection with the hickory.
Mr. Pomeroy: I haven't ever tried any experiments with the hickory.
President Morris: We will discuss further some of the points that have
been suggested in this paper, because it seems to me we are along a good
line of cleavage, and this line of cleavage may dispose of some
questions that we haven't discussed. One question brought up was if the
bitter, astringent qualities are likely to be recessive among hybrids in
the trees which have bitter nuts.
Mr. Littlepage: I made a trip through Missouri and Arkansas a year ago,
and while there, took occasion to go into the forests, and investigate
to some extent the Arkansas and Missouri hickory and pecan. Among other
things, I found two hybrids, one of the pecan and one of the pignut, one
of which was bitter and inedible, the other a fairly good nut. I have
both of them with me here today. One of them was very astringent and
bitter, the other had taken more the quality of the pecan as to meat,
and was a fairly good substitute. I don't know what the reason for it
is, that one is fit to eat, and the other isn't, when they are both
hybrids between the pignut and the pecan.
Doctor Deming: How did you know they were hybrids, by the appearance?
Mr. Littlepage: Yes, the appearance is unmistakable. The pignut
characteristics are very prominent, also the pecan characteristics.
President Morris: Have the members anything to say about the
Stringfellow method of transplanting hickories?
Doctor Deming: I have had very little experience in transplanting
hickories, but I set out two Hales hickories I got from Meehan, and they
are both living, although they have made little growth in some three
years. Can you tell us what stocks the Hales hickory is grafted upon?
Mr. Brown (Pennsylvania): Upon the bitternut. All there are have been
upon the bitternut from the start.
Doctor Deming: Mr. Littlepage, what do you think of the future of
topworking our seedling hickories in the North with improved varieties
of hickory or pecan,—the commercial future?
Mr. Littlepage: It is largely speculative. I suppose it is the province
of every nut enthusiast to have an opinion about these things. In fact,
I find it is encouraging to talk to the fellow who has an opinion. My
notion is that there is a great future for topworking the various
varieties of the hickory in the North to the desirable forms of the
hickory, that is, of the hickory other than the Hicoria pecan. On my
farm I expect next year to devote some time to topworking the various
hickories I have to the desirable varieties of the shagbark. I think
that can be done throughout the whole country. The shagbark seems to be
indigenous to such extensive latitudes, that it seems to me there are
great possibilities along that line. I observe that around here we find
many of those trees. I have some very beautiful shagbarks that came from
Canada. My opinion is that it will be successful. I think the reason the
pecan has not proved very satisfactory upon the other species of hickory
is that most of those hickories have a close grained wood, and that the
distribution of available food depends largely upon the amount of sap.
The Hicoria pecan is a much coarser grained wood. The flow of the sap
upward is facilitated much more than the flow of the sap upward through
the hickory stock of other varieties. I believe that is the reason the
theoretical rule would probably not work in this case, simply because
the distribution of sap cannot take place fast enough through the tight,
close grained stock of other varieties of hickory. Otherwise, I don't
see why the rule would not obtain, as with fruits. The experiences Mr.
Reed gives, I think, are generally recognized by those who have
experimented with them to any extent. I noticed in visiting Mr. Roper's
nursery he had one very beautiful specimen of the pecan grafted on a
hickory. That was the Stuart, was it not?
Mr. Roper: The Moneymaker. It had made a growth of four or five feet in
two years.
Mr. Littlepage: Do you know the variety of hickory that it was topworked
to?
Mr. Roper: Just our common hickory, I suppose the pignut.
Mr. Littlepage: It made beautiful growth from the wood standpoint.
Mr. Roper: Mr. Reed's point was that it would do that till it got by the
period of good nutrition from the root. Professor Craig says the
elaboration of food from the pecan top more than overcomes the
deficiency.
Professor Lake: I would like to question Mr. Littlepage's physiological
ground for the lack of proper fusion of liquids between the pecan and
the other hickories. I believe it is not authenticated that the water
supplies from the earth would not distil as fast in the close grained
hickories as in the more open grained pecan. At least, the very close
grained, firm woods of the tropics transmit a tremendous amount of
water, much in excess of many of our fine grained woods of the North.
And it seems to me I wouldn't like to have this Association go on record
as vouching for this explanation exactly. It seems to me there are
better explanations. Lack of fusion is not due to the amount of water
that is carried up, but rather to the fact that the root system of the
hickory does not develop fast enough to collect water to transmit.
Mr. Littlepage: I am very glad to hear Professor Lake's statements. My
suggestions were given only as a possible theory that occurred to me,
and I don't vouch for their accuracy. There must be some explanation to
controvert the general rule which Professor Craig has given us.
Professor Craig: May I add one word? When a stock and scion unite, the
union is really a mechanical one. It is a union of cells, and in that
respect it is simply mechanical, not a physiological union. The
different life types or character of the scion and top do not fuse, but
we have a mechanical union of cells, and that mechanical union is as
clearly shown forth as possible when we make a section through the point
of union. If your type of cell in the stock differs very materially from
the type of structure in the scion, the union is unsatisfactory. If the
types of tissue are much alike, the union is good and you do not have
either overgrowth of stock or undergrowth of scion very much, but you
have what is called a good union. It is to some extent a question of
mechanics, in my judgment, influenced by the cell structure of stock and
scion. If you have a good, smooth union, the two grow equally. Where you
have overgrowth of scion, you usually have a starved root, because the
food which is to be returned elaborated is checked at the point of
union, the root is starved, and you have a short lived tree, because
your root system, which ought to receive its share of the distributed
food, is underfed, finally weakens, and the whole structure fails.
Professor Lake: You may have mechanical union, but you can't have the
after fusion in which you are going to have proper function of stock and
scion.
Professor Craig: Each cell functions after its own kind. It is a
question of passage or transmission of food through that carrier, after
the union is effected. If the character of the two types differs very
much, the transmission of food is checked and is difficult.
President Morris: There is another mechanical point I'd like to ask
about. When the two types of cells differ, will the difference in degree
of capillarity regulate the amount of pabulum distributed, or does it
depend upon negative and positive pressure?
Professor Craig: That is a very difficult question, because it isn't
settled at the present time what credit we should give to capillarity
and what to root pressure in sap circulation.
Mr. Reed: There is another question I would like to ask Professor Craig.
Supposing you have a mechanical union perfected, what is the difference
in the food that different species of the same genus transmit? Has that
been worked out?
Professor Craig: I don't think so. Of course, there is a difference in
the food. That is proven, because there is a difference in the quality
of the food. The tree machine, the tree factory speaking individually,
evidently makes different products, and that is shown by the different
quality of nuts. That is all we know about it.
Professor Lake: That part below the scion still continues to be normal
hickory, and that part above, pecan, so really it is not a matter of
distribution of water supply by gravity or other pressure, but rather a
distribution of the proper amount of elaborated food; and that is
transmitted through the cell itself, not the cell walls. Because this
top makes a food that is different from the normal requirements, or
because the latent character of those cells below does not respond to
the food supply as actively as the part above, is the whole question, it
seems to me. If the cells below functioned as the cells above, there
would be no question about the stock and scion being the same.
Mr. Littlepage: Of course there must be sufficient flow of sap to
distribute food. The hickory root might not send the flow of sap as fast
as the pecan top would like.
Mr. Reed: Is Mr. Lake's point always true, that the stock below the
point of union remains a normal hickory?
Professor Craig: I don't believe there are more than one or two
exceptions noted to that, and those exceptions are recorded under graft
hybrids.
Mr. Reed: A seedling pecan tree owned by Mr. B. M. Young of Morgan City,
Louisiana, was top worked with scions from the McAllister hican some
seven or eight feet above ground, and later on the bark of the pecan
trunk below the point of union became scaly like that of the hican
above.
Professor Lake: That would suggest something worth while, if that part
below would produce fruit like the part above, but I would want to
question a little the modification in bark characteristics being a
direct result of cross grafting.
Mr. Reed: Of course, it was no check—only one instance.
Professor Craig: There are one or two others that are authentic. I have
known a case of plum. Here we have the plum stock, we will say it is
Prunus Americana, grafted with Prunus triflora, the Japanese, then
later on, Prunus domestica is put on top. I have seen a sprout from
triflora bearing Japanese plums, while the top of the tree bore Prunus
domestica, although there was only a small section of stem in there
between our two distinct species. They were perfectly normal.
President Morris: Each elaborates its own kind of food in its own kind
of cell. I would like to hear from Mr. Brown and Mr. Wilcox on this
matter of grafting—the influence of stock on scion.
Mr. Wilcox: We had a good show of stocks, but instead of allowing them
to become established in the pots, we grafted them as they started into
growth after rooting. Had they been established, we would have expected
better results.
Professor Craig: What method do you employ?
Mr. Wilcox: Side grafting.
Professor Craig: Do you mean whip grafting?
Mr. Wilcox: Side whip grafting.
Doctor Deming: I would like to ask Doctor Morris what he thinks of the
practical future of grafting our hickory seedlings with improved
varieties of hickory or pecan, and the method most likely to
succeed,—whether grafting or budding, and at what season. It is
important to learn whether we can so graft or bud our hickory sprouts
that within a few years we can hope to get something from them.
President Morris: We can only make a parallel with the pecan. If we know
that it requires fifteen or twenty years for coming into bearing as a
seedling tree, and if we know that it bears frequently in two, three, or
four years after being grafted we can anticipate analogous action with
other species of hickories. I haven't been able to get testimony from
men who have grafted hickories. One man told me he thought shagbark
grafted upon other shagbark, topworked, came into bearing in seven or
eight years. Another man told me that his came into bearing in a much
shorter time than it would otherwise, while with one particular variety,
the Hale, I think that twelve years has been required for the tree to
come into bearing.
Doctor Deming: I have a communication from Mr. Hales in which he speaks
of a tree grafted in 1880, but doesn't say when it began to bear.
Mr. Littlepage: He told me it has taken some of them twenty years.
Doctor Deming: But the pecan on hickory has been known to bear the
second season, that is, topworked. Can we expect such results in
topworking our own hickories?
Mr. Littlepage: I think so.
Doctor Deming: Are we going to have success in topworking, and by what
method?
President Morris: I believe in the South they can graft, but in the
North we have got to do it by budding. My best results have been late
July or early August. I believe herbaceous budding promises a good deal.
Mr. Rush: Were those buds then of the year previous?.
President Morris: Those were buds from the year of the scion, and
herbaceous stock of the year.
Doctor Deming: Mr. Littlepage has had some success in budding hickory
very early, haven't you?
Mr. Littlepage: I was just stating that I started in last year to bud. I
think it would be possible to make a pecan orchard bear early by budding
into these hickories, ten, fifteen, or twenty years old. This next year
I am going to try hickory on hickory. I am going to try three processes.
I am going to try bark grafting, and whip grafting in the body of the
tree which has been cut off. Then, I have quite a number of hickories
each four or five inches in diameter that I have sawed off and allowed
to put up clusters of water sprouts, and I am going to whip graft some
and put paper sacks over them, and see which is the best.
President Morris: I have found budding the best.
Mr. Reed: Doctor Morris referred to the analogy of the pecan grafted on
pecan as coming into bearing in two years. Do you account for that in
the fact of its being a graft, or the fact that the wood you selected
came from a tree that had the characteristic of early bearing?
President Morris: No doubt that characteristic was transmitted, and
further, no doubt the grafted stock was used from bearing wood. Those
points are all of interest.
Mr. Reed: Does the mere operation of grafting or budding influence
earliness of bearing?
President Morris: Yes, if I understand the question rightly. A tree that
might not bear for fifteen years as a seedling may bear in three years
grafted.
Mr. Rush: I have Persian walnuts that bore two fine nuts the second
year. I have young trees, one about thirty inches, and I am sure it
will be full of nuts next year, unless some providential misfortune
should intervene.
Mr. Reed: At what age did the original trees begin to bear?
Mr. Rush: Those were buds shipped to me from California.
Mr. Littlepage: I am firmly convinced that there is something in the
process of budding or grafting that stimulates the growth. For example,
I have scions that were not over four to eight inches long grafted on
one year seedling pecans which, at the end of this season's growth, were
as much as thirty inches high. All along in the same row where seedling
pecans were not grafted, there is none over eighteen inches high.
Mr. Reed: To have made exact comparison, you would have had to take buds
from your seedling nursery trees, and graft on other trees. You are
comparing these buds from one tree with seedlings of another.
Professor Lake: I would like to ask if you didn't bud or graft the best
stocks in the row too?
Mr. Littlepage: We took the whole row, as we came to it, but that
particular tree might have been on some particularly favorable stock. It
is a matter of a good deal of interest to see why a seedling which
wasn't budded at all didn't grow as high as a scion which was budded in
summer, stratified all winter, then put into the ground in an unnatural
position.
Professor Craig: It is the same principle, I think, which we discover in
pruning. If we prune heavily during the dormant season, the effect is
increased vegetative growth. If we wish to stimulate the growth of an
old tree somewhat debilitated, we go to work and cut off a large portion
of the top. We don't disturb the root. The effect is that with the same
amount of pushing power from the root, we have a decreased area over
which that energy is spread, and it results in apparently increased
growth. I am not quite sure if we were to measure it up in a scientific
way, we would actually find it was increased growth. There are fewer
branches, but they have made greater length. In the case of grafting our
pecans, we cut off our tops, set a two-bud scion in the root, and
usually but one starts and receives all the vigor from the established
root, instead of the vigor being distributed over several buds on the
original seedling top. We have as a result of that concentration of
vitality increased growth. I think that theoretical explanation will
stand fairly well, because it seems to be directly in line with the
effect of winter pruning.
Mr. Reed: I would like to ask Professor Craig to what extent he would
select seed for nursery purposes? What influence would the characters of
the parent tree from which the seed came have on the grafted tree?
Professor Craig: I don't believe that we can expect the characters of
our stock to affect the scion to any extent. I think what the nurserymen
should have in mind and keep in mind is a good, vigorous stock, and as
many stocks as possible,—as he can get out of a pound of nuts.
Otherwise, I don't think it cuts much figure. In that connection there
is a principle which I have discovered by experience, namely, that if
you are growing stocks it is wise to get your nuts as near your own
locality as possible. My experience last year in planting five hundred
pounds of northern grown nuts in a southern locality, and five hundred
pounds of southern grown nuts in the same locality, gathered in that
locality, is that I got fifty per cent more trees from my southern grown
nuts than northern, and trees that were fully thirty per cent better.
Mr. Littlepage: Where were your northern grown nuts stratified?
Professor Craig: They were not stratified. They were planted as soon as
they were received, and they were received within two weeks from the
time they were taken from the trees.
Mr. Littlepage: I am inclined to believe that if your northern grown
nuts had been stratified in the North, and undergone the customary
freezing and thawing, then had been taken up in the spring, you wouldn't
have seen that difference.
Professor Craig: I think that point is well taken.
President Morris: There is no doubt about that. In that same
connection—I would choose nuts for seed purposes of a mean type, for
the reason that nature is all the while establishing a mean. The big
pecan is a freak. If you plant big or small nuts, you don't get big or
small nuts in return. You get both big and little seeking a mean.
Mr. Roper: The large nut will give a better tree. We have tested that
out.
President Morris: Does that work out logically in that way, is it a
comparative matter all the time?
Mr. Roper: We haven't worked that out in the bearing, but in the nuts in
the row, the small nuts did not produce as large trees as the large
nuts. We never tested the mean nuts. We did select some of the very
smallest we had, and planted one of the northern and one of the southern
type. They came up, but the trees amounted to nothing.
President Morris: The idea I meant to convey was that both very small
and very large nuts are freaks, and neither likely to give as good a
tree as mean types. What would you anticipate, Professor Craig?
Professor Craig: I think that would resolve itself on a practical basis
from the practical standpoint. I think the mean or average sized nut
would give you the best results. There is no doubt, as Mr. Roper said,
the very small nut would give you weak seedlings. On the other hand, you
couldn't afford to use the very largest, so that a mean between large
and small would be the natural thing to choose. But we should do nothing
to discourage the planting of the finest specimens, with the possibility
of getting something unusually good. That is certainly the work for
every amateur.
Professor Lake: Does that statement, that you think it doesn't make much
difference about the parent of the nuts for stock, apply to walnuts?
Professor Craig: I haven't had any experience in walnuts.
Mr. Littlepage: I would like to ask Mr. Roper if he knows of any
examples where selection of fine varieties of seed has not resulted in
getting a more productive variety of the plant which he was producing?
Mr. Roper: Only one, and that wasn't in a tree.
President Morris: In regard to coming true to type, I think records have
been made of many thousands of pecans, and I don't know of any instance
where the progeny resembled the parent closely.
Mr. Pomeroy: Maybe someone could explain one of my failures a few years
ago in planting some Persian walnuts. I went to another tree in western
New York, and got a peck or more. They were planted the same day, in the
same ground, and all came up. Those I got from another tree resembled a
hill of beans, and stayed that way for three years. Why wouldn't those
grow? In soil three feet from those, there were trees growing. Those
nuts never did make trees. The nuts were of good size.
Colonel Van Duzee: As a practical nurseryman, I wouldn't think of
planting nuts from a tree that I didn't know individually. We have had
very much better success with nursery stock where we have chosen as seed
medium sized nuts from vigorous trees with which we were acquainted. In
the case of Mr. Pomeroy, I don't think there is any question but that
the history of his tree would account for the failure. In other words,
his nursery stock was undoubtedly from the results of years of slow
growth on the part of the original tree, or unfavorable conditions of
some kind. I don't quite agree with Professor Craig on the question of
the influence of stock, because I believe it is really a very important
point.
President Morris: We are not here to agree upon anything.
Colonel Van Duzee: I can't speak from the scientific standpoint, but I
am quite sure that in the nursery business I shouldn't care to overlook
that influence.
President Morris: When men agree, it means we are on stale old ground
which has been thrashed over.
President Morris: The meeting is called to order. The first paper this
afternoon will be that by Mr. J. Franklin Collins of the United States
Department of Agriculture, on the chestnut bark disease.
