Discussion
MEMBER: 300 board feet per acre per year?
MR. WALTERS: I said we felt that on good soil and by encouraging nature we can grow that volume.
MEMBER: What are the stumpage prices?
MR. WALTERS: Ranging from about $10.00 per thousand board feet to $300. There is quite a span and each grade is different. There is a prime grade, which is the best grade, which must be 16 inches in diameter at the small end at least. Each company has a little different set of grades. Even with the same grade the prices will range according to the size of the log. Maybe a 16 inch prime log may be worth $200 per thousand board feet and 24 inch will be $300.
MR. CRAIG: Curly walnut would be worth more?
MR. WALTERS: Yes. It is somewhat of a guess as to whether a tree will have a curly figure. If you let them take the bark off a tree, the buyers can tell. I know of one beautiful stump on which the buyer wanted permission to remove part of its bark to see if it had nubby growth. If it had had the figure, it would have been very valuable. The farmer said, "I don't want you cutting on that tree because if it doesn't have the figure and you don't buy it, the tree will be spoiled." Don't let the buyers chop into the tree to see whether it has figure.
MR. CRAIG: I bought two to get grafting wood.
[Editor's note: Mr. Craig refers to the Lamb curly black walnut, article on which appeared in NNGA 39th Annual Report.]
MR. WALTERS: There has been some work done on grafting or stimulating growth for figure. One method was to beat the trees with a rubber hose and try to stimulate figured or curly grain. Not too much has been published on this work as yet.
MEMBER: Do you think the figure could be propagated by asexual propagation?
MR. WALTERS: I don't know. I will say this; in forest trees, the inherited characteristics are the things we depend upon. If a tree has curly figure and the seed carries that characteristic, you may see it in the progeny. An acquired characteristic I don't think you can depend on so much.
MEMBER: Is it thought to be acquired or hereditary?
MR. WALTERS: I just don't know whether it is acquired or hereditary.
DR. ROHRBACHER: One thought came to me on this black walnut timber. It's a long pull, and it is one for our posterity. The thought came to be that it is for those of us who are interested in setting up something for our offspring. The plan has been brought out before of using a grafted known name variety of nuts. Plant those, and perhaps those trees as they grow would first give us that wonderful nut which we were looking for.
Symposium on Nut Tree Propagation
F. L. O'Rourke, Leader
MR. O'ROURKE: I believe if you get 10 nut people together, you are going to have eight or nine propagators. It is the one thing that people like to dream and talk about.
I went through the list a little bit, and in order to save some time I wrote a resumé of what had been done. In order to accumulate that material I had to dig into some of the more or less unused volume. There is a wealth of information in some of those earlier reports of the Northern Nut Growers Association.
MEMBER: You can get them for $15 a set.
MR. O'ROURKE: It's a good investment anyway. At any rate, I think I am going to try to make a bit of an analogy. Suppose this was a church group who had been working on paying off their mortgage. Every once in a while they passed a hat, but instead of dumping that hat on the table they let those contributions accumulate, so that after a while they had the accumulation of 41 years in the hat. Someone has to dump the hat sometime and I tried to do that this summer, and I found all sorts of contributions in that hat. We might say this happened to be the hat. You would find some brand new fresh ten dollar bills, nice new currency, and then you would find some gold pieces (before Roosevelt). They too can be used because they can also be converted. Then you could dig back and come across some stuff, and you didn't quite know what it was. It might be a Spanish doubloon or an old brass button. Right there is where you need a little knowledge. You should be able to tell the difference. I don't know whether I was able to tell that difference. We will, of course, find a lot of slugs and buttons and this and that among the valuable pieces, so possibly we should sift those out and put them in the discard. You never can be sure what to discard.
Just as I said, every nut grower is a propagator at heart. A little wee paragraph may be a lead to something which would be of quite a lot of value.
This little brief resumé I passed around yesterday, and now this morning I am using my school teacherish techniques in passing around a sheet of paper. There is merely an outline. Pardon me if I insult your intelligence in getting out that outline. As you notice, we start out with the seedling and end with nursery practice. This outline should fit almost any nut species. It should fit chestnut, hickory, walnut or any. I thought it might be best to have a vote as to which one we talk about first, and then we will run down each particular species. I think we should have our panel come up front.
As I said a while ago, we know that practically every person in this room is a propagator. In order that we have this panel conducted in an orderly way, please raise your hand when you speak. I will get the question and pass it to one of the panel members. Which one shall we take up first?
MR. McDANIEL: Let's take the hard one first, the Chinese chestnut.
All right, chestnut. To be systematic, let's talk about seed. Anyone having any difficulty? No trouble at all. Who grows most of the Chinese chestnuts, germinates most of the seed?
MEMBER: I have trouble with rabbits, squirrels, ground hogs.
MR. O'ROURKE: He wishes to know of something to protect his chestnuts.
DR. McKAY: We don't plant in the Fall. I know of one person who uses red lead. We have never used it. I know that has been done. We store our chestnuts in cold storage over the winter and plant in the Spring.
C. S. WALTERS: May I interrupt? We tried 50 chemicals, treating walnut seed with them or putting them on the seed spot after the nut was planted. The squirrels lifted every nut except those that wouldn't have germinated anyway. The rascals knew the difference. We tried allylisothiocyanate—"tear gas." The squirrels would dig those nuts up and when the vapor got too strong they would go away and allow it to evaporate. Within two weeks they would come back—maybe two or three times—before they finally took the nut. We tried cayenne pepper and n-butyl mercaptan—the main ingredient in "polecat essence." We had squirrels all over our test plots, and the only nuts they didn't take were the bad ones.
MEMBER: I have had every other kind of rodent. I found I have to plant in the spring and always in a tin can, with rock wool over the nut.
MEMBER: We have used rock wool; planted in the spring. They will get them any time.
MEMBER: I did the same thing with chicken wire and no squirrels got them.
MEMBER: I would like to ask Mr. Chase if he has planted chestnuts on a quantity basis.
MR. CHASE: We planted them on a quantity basis and as some of you know our nursery is adjacent to a wooded area where you would assume there would be a lot of rodents and polecats, both kinds—four and two legged. I made that statement once before about never having had any squirrel damage. We don't have any trouble. We do not lose chestnuts. We mulch with composted mixtures.
MEMBER. They claim sawdust will help keep them away.
MR. CHASE: On the other hand, a gentleman wanted to get started with chestnut in the Smokies. We helped him get lined up and he planted in beds and these are perhaps a hundred feet long. We mulched heavily with sawdust. The area had been cut over six to eight years ago and had immense piles of sawdust. We mulched with about four inches and some animal got every chestnut out. We never knew what animal it was. There wasn't any evidence on the top. They got every chestnut which was quite a shock to him. I brought this point out that there was danger and he was going to build the bed up high and cover with wire or he was going to get some of this old camouflage netting type and cover that bed for protection both against rodents and early spring frost. He didn't follow through on that so I don't plead guilty.
MEMBER: Does the Chinese chestnut seed have a rest period?
DR. McKAY: For some years we have had a friendly discussion with the Division of Forest Pathology in regard to whether a chestnut seed has a rest period in the same way black walnut, hickory, or some of the others do, and we are not absolutely set in our opinion on the matter. We have the opinion that the Chinese chestnut does not require a rest period. I will tell you that one species, the Allegany Chinkapin (C. pumila) will germinate very readily as soon as it is matured. It will start growing immediately. When you go into the oak species, you have a number like that. They fall to the ground, and put a root into the soil, become anchored, and grow slowly all winter long. We feel that the Chinese chestnuts are of that type. Perhaps the old American chestnut was that way. It fell to the ground in the fall and it sprouted rather promptly within a month or so and grew slowly. Perhaps the Chinese chestnut is not so much inclined that way. We have done this: we have taken them from storage at various times during the winter and planted them, and have never failed to get reasonably good germination. Others have. The results there vary considerably. Perhaps we can't be too sure about the matter. We simply feel that on the basis of what we have seen and observed, they do not have a definite rest period. Many of the failures that have been obtained have been due to poor storage conditions, where the nut started to spoil and perhaps the workers didn't realize it and planted that nut and the nut spoiled immediately. So you fail, not because of the inability of the seed to sprout, but because it was improperly handled and could not grow.
MR. O'ROURKE: Is it not a fact that ... seed has no true rest period as we know it with trees? On the other hand, about 30 days' exposure to low temperature and moist conditions will cause all those seeds to germinate immediately. It may be somewhat the same with chestnut seed.
MR. STOKE: In confirmation, I furnished a man some seed some years ago and we put them in flower pots and they were a foot high by Christmas.
MR. McDANIEL: The growth is normal from the immediate planting, too. You don't get the suppressed growth later, as in prematurely germinated peach.
MEMBER: The chinkapins will often sprout even before they come out of the bur.
MR. CRAIG: I might say this concerning the California Persian walnuts. Take one at harvest and plant it, and that seed will germinate immediately. You hold it in dry storage and plant in the spring and it will come up in a couple of weeks. I speak from experience.
DR. CRANE: The same thing is true with pecan, in west Texas and Arkansas and California. We have lots of trouble with pecans germinating. It is not uncommon to find a pecan germinated with a root as much as ten inches long grown in the hull. If that nut goes through to maturity and becomes dry, then there is an appreciable delay in germination. They won't germinate as quickly. There has got to be a lot of changes in the kernel after they have once dried out and been harvested before germination will be initiated again.
DR. McKAY: In connection with this question of germinating nut seeds of all kinds, we think it is very important to plant the seed in a well aerated medium. I think that is a mistake many people make. If the soil happens to be of a clay nature, it keeps out oxygen and air and the sprout will rot. That is the reason why, when we plant chestnut seed, we like to plant in sand or the same with any nut seed. Coarse sand has a lot of air in it. That nut has a high demand for oxygen.
MEMBER: In the matter of chestnut seed, don't put too many layers of seeds. One is better than two. Even in rather porous soil, they seem to develop gas. Anyway, I found the bottom ones didn't get enough air and they rotted, whereas on top they didn't. It is better to plant a single layer than more.
MR. SHERMAN: What is the best method of treating the chestnut seeds in the fall to prevent the development of weevils?
DR. McKAY: Of course, there are several ways of treating the nuts for weevils. One is the old hot water method. All of us can heat water. We have to heat it to about 120 degrees. So hot, you can't hold your hand in it. Immerse thirty minutes for an average size nut. Now in connection with the spoilage and rotting that is another matter. We believe in harvesting chestnuts promptly, storing them before they dry out. We of course store our chestnuts in cans. Cans with lids and holes punched at either end.
MR. O'ROURKE: Are there any other questions pertaining to seeds?
MEMBER: I would like to caution persons outside the weevil belt about being very careful if you get nuts that may be infested. Leave your nuts in a small jar and you have the advantage of watching the weevils actually emerging. You can pick the nuts out about February, and you can select all the nuts that are sound. Once in awhile a weevil will live through the winter. One thing we should all be thinking about is that the nurseryman has to produce grafted trees in order to fill a demand, and those nut trees must be produced cheaply and he must use methods which are highly efficient.
MEMBER: Has anyone tried to deep freeze?
DR. CRANE: We tried that just this past winter. For a couple of years back one individual had asked us why we didn't freeze them. Last winter we did. We stored three gallon buckets at two temperatures. One at zero and the other at ten degrees below—hard freezing temperatures. Those nuts stayed frozen from early October until the next April. We brought them out and examined them one morning. The first thing we did was taste them. Those nuts we ate when first opened and you could tell them from no other chestnuts. They were nice eating, sweet. We let those chestnuts thaw evenly at room temperature. That evening we examined them and it's hard to describe what the transformation was in those nuts. In the first place was the deterioration that had gone on as soon as the tissue thawed ... They were dripping water. The tissue had burst and the water just flowed. On the other hand, about an hour after they thawed out, when we first examined them just as they thawed out, you would be amazed at how tender they were. They would melt in your mouth. Freezing apparently breaks down the tissue. The tissue is as soft as it can be. Apparently this freezing transformed some of the starch to sugar. The rub is that it won't keep for even two or three hours.
MEMBER: They might keep if you put them in the soil first.
DR. CRANE: The tissue is ruined.
MR. O'ROURKE: We have now decided certain things pertaining to seed germination. Then we are confronted with the problems of seedling versus clonal rootstocks. I do not know whether or not there have been clonal rootstocks selected for Chinese chestnut. I am sorry to have to ask Dr McKay to talk again but he knows more about it.
DR. McKAY: I can only tell you about the experiment we started this spring on clonal stocks of chestnuts. We have just this year's results. Unfortunately we didn't get good results. We took ten seedling trees. We used nursery trees, large five-year old trees, with vigorous root system, ten seedlings, and got from them 20 roots. We took roots the size of your finger with a lot of feeding roots, and we grafted onto those five times four. We took four per variety. We used five varieties of chestnuts, and all five of those each had four pieces and we had ten of those seedlings. We wanted to find out whether any of those ten seedlings would give us a better set of these five varieties than any other trees. In other words, we are trying to get a start on a clonal rootstock. We used a splice graft. We simply took a piece of scion and spliced it right on the end of the root. We had four of those in the bundle, and we had five per seedling and we had ten of them. That made 20 in all. We planted in a cold frame, with cheesecloth covering to keep the temperature from getting too high. Eventually, if this thing works, we will establish a clonal line. We planted those ten original trees but you will be surprised. We can go back to the original tree if we succeed with clonal lines, so a chestnut variety we hope will be grafted on a line of stock that came from that one original tree. Bear in mind this is the method and it remains to be seen whether it is going to work for chestnuts.
The results are discouraging. Only one or two seedlings gave us six or 8 successful grafts on all the five varieties but by that method of trying all five of these varieties on all ten of the seedings we hope to get a start. We will try them again, and we hope to get at least a start that will work. It may be that we will have to start over again. We may want to take ten other seedlings. That is, in brief, our work so far in that direction.
We took it off the ground. We didn't have long enough side roots.
MEMBER: How about mound layering?
DR. McKAY: We tried cutting off at the ground level and mounding up those sprouts and tried to root them, with no satisfactory results. There was just a small amount of rooting.
MEMBER: Did you try layering?
DR. McKAY: One year we did, but with no success.
MR. McDANIEL: I have seen a few layered successfully but it's a little slow.
MR. O'ROURKE: Shall we move to vegetative propagation and consider cuttings first?
DR. McKAY: Just one thing I think ought to be mentioned at this time. We know that even the use of clonal rootstocks does not entirely eliminate variability. All the work that has been done with these Malling apple stocks shows that, as far as apples are concerned. Now we have an idea which, in a crop like chestnuts, may have very far reaching influence and we feel quite hopeful for it. That is growing seedling progenies of certain parent trees. I want to tell you our experience with it. We started our work on breeding and selection of tung nuts in 1938, and we have tested now over 600 parent trees that were especially selected. Out of those six hundred we have released a total of six horticultural varieties, for asexual propagation. But out of those six we have three trees, the seed of which will produce seedling progenies that come very true to the type of the parent tree. One of those released we know as the Lampton variety. It will produce from 95 to 100 per cent of its seedlings, that are so true to type that you can identify them in the nursery. At the end of the first season you plant 95 to 100 per cent of the remaining trees in the orchard and anybody can identify the trees.
In the case of budded trees we have the variability of the rootstocks, which affects the growth. Since that particular variety has been released there has not been one single nut of that variety crushed. Every single seed is grown to tree size, to plant in a new orchard. It has taken us 12 years to reach that stage, but that one variety is probably the most outstanding thing we have. There is a slight variation in the trees but not as much as you have in other trees.
Now, with Chinese chestnuts, we planted seedlings that were grown from the seed of a parent tree at Beltsville. We planted a thousand trees. There were seedlings grown from seed produced by different parent trees. Out of those thousand there wasn't a single one outstanding. Yet in one lot of seedlings which was planted in Georgia, every one of the seedlings grown from the seeds of that selected tree produced such high quality nuts that we haven't cut out a single tree. There just hasn't been any off types. Now we have gone a step further. We had one called selection 7932 which came into bearing very early. We have had those trees grown from seed. The seedling at three years of age produced a pound of nuts, the seedling having the characteristic of its mother. We have hopes that before many years we shall be able to produce parent trees or clonal lines in which the seed taken from those line and planted will give us uniform seedlings.
I don't want you folks to get the idea we have these parent trees or seed from them that are available. I mention it because a lot of you are growing chestnut trees and planting them from seed. You could make a great contribution if you would take the nuts from each individual tree and plant separately, so that you will know in the future the origin of every one of those seedling trees you have. Some of these days someone is going to find one that is going to give us seedling trees that are good and free from variation.
Elberta peach seed will come practically true to variety from seed, except minor variations of size, shape, color and season. In a peach you are facing a very highly specialized market. But with the Chinese chestnut, color is not so important. What we are interested in is trees that bear and have enough uniformity so that we don't have pee-wees by one and jumbos by another.
We need very badly this sort of thing. We need chestnut varieties planted in pairs in isolated places. Any of you folks could do a great service if you will let us know wherever trees occur in pairs, or just two varieties and no others, and then we know that one variety pollinates the other. When you have a mixed planting of a half dozen varieties the male is promiscuous. Therefore you have a much greater mixing of genetic factors. If we have a pair of trees, we get a much more uniform breeding group of seedlings.
MEMBER: How far removed from other varieties do they have to be?
DR. McKAY: Half a mile or a mile.
MR. O'ROURKE: I think we can go to vegetative propagation of cuttings. I think that we have any amount of evidence that Chinese chestnuts can be rooted from cuttings, but can trees grow on from rooting cuttings?
DR. CRANE: You have summed up the situation perfectly.
MEMBER: Just by accident, in our storage house a couple of chestnuts fell over into a pile of peat moss and they did make roots.
MR. CORSAN: Would you call the Chinese chestnut a second?
MR. O'ROURKE: We should confine this only to propagation. While there are any number of interesting phases of it, we have to stick to propagation or we will never get through. We have had remarks on layers. Any comments on layers?
Let's move on to graftage. We want to have our chestnut produced on a quantity basis so I am going to ask Mr. Bernath to tell us a good method.
MR. BERNATH: I don't graft too many outside, but I do my propagating in the greenhouse. I had more than a thousand graftings growing, some of them this high [indicating] which greatly depends upon the root system and the condition of the soil. I think that is the fastest and easiest way of grafting chestnuts. I do my grafting sitting down.
MEMBER: That's on the potted stock.
MR. BERNATH: That's right.
MEMBER: After you have produced all these grafts, what are you going to do with them?
MR. BERNATH: Sell them.
MR. STOKE: I tried to contact some nurseries. They are selling your seedlings, little chestnut trees for $1.75 and they want to give you 75¢ or a dollar for grafted ones.
MR. O'ROURKE: Mr. McDaniel has received a letter from Mr. Hirschi from Oklahoma City and there is one paragraph that I think the membership will be interested in. [Letter from Mr. Hirschi is partly reproduced here.]
Oklahoma City, Okla.
Aug. 23, 1951
Mr. J. C. McDaniel,
Urbana, Ill.
My Dear Mac;
... In my work with chestnuts I believe I have had an experience that will be interesting to the membership. As you well know I am a strong believer in selected named varieties. I do not regard seedling chestnuts any more valuable than seedling peaches or apples. The—Nursery, a member of our association, have been customers of mine for a long time. Last year I persuaded them to catalog seedling chestnuts at about half the price of Nanking, Meiling, Kuling, and Abundance. I was anxious to learn the attitude of the public, where they had an opportunity to buy and plant selected grafted varieties, when heretofore only seedlings were available. To my utter amazement the seedlings did not sell at all, but the thousand trees of selected varieties were sold out long before the season was over. I could not supply more, neither could I get them elsewhere. So far as I know Max Hardy and I are the only ones grafting chestnuts in quantities.
It is amazing the volume of business that catalog nurseries do. For instance the above firm does a million dollars gross business annually, and many others do a big business. All would be glad to catalog grafted chestnuts, and the chestnut movement would grow by leaps and bounds. True, they would have to be sold to them at wholesale prices, but they want small sizes, parcel post sizes preferred, which can be produced the second year from seed. Plant the seed in March, the next March graft them, and by fall the grafts will range from three to seven feet as shown by the enclosed photos.
I had the same experience with the above firm with Carpathians, sold them 500, which were sold out long before the season ended and I could not get them any more. They have ordered 2500 for this coming season. Unfortunately we had a poor take on grafts this spring due to cutting scion wood after a November freeze, which killed all other English walnuts. Carpathian wood was not hurt except where used for scions. Where left on the trees they forced out as usual and are producing a good crop of nuts.
I must close. I know you will have a wonderful meeting and I wish I could be with you. I will be with you in spirit, and in the meantime will be doing all I can to promote interest in nut growing.—Very truly yours, A. G. Hirschi.
MR. GERARDI: I don't yet have the greenhouse. I depend on field grafting. I produce my own seedlings. I just use seed from those three best trees. They run pretty uniform as far as growth is concerned. I bark graft in the field, when the buds begin to swell nicely and from there on. You can get a growth like that. [Indicating four to 5 feet.]
MEMBER: He has the same thing. Just as soon as the buds swelled. Sometimes I do go to the trouble if I am covering more ground, to cut them off as soon as they start to swell. A chestnut will peel again in four days. I start in after about four days and set these grafts and I use this bark graft. I have a sample of the method here. This is the plain bark graft which is efficient and fast for the production of chestnuts in quantity. I have to get into bigger production. I am trying to make speed and I am using this method. To start, the first week of April, when the buds start. If I get it done, it's the first week or the second of April.
MR. GERARDI: Four days on chestnuts. In my personal opinion after a few years observation I don't believe it is absolutely essential to cut back. Sometimes weather conditions will be a big factor. Sometimes the temperature is around forty and remains that way four or five days. The weather has taken the place of your cut back. That doesn't always happen, but weather conditions sometimes favor this.
MEMBER: What percent of failures do you expect on a hundred?
MR. GERARDI: Well, it is better to take a thousand trees. Out of a thousand you miss 35 or 40. The percent that takes is high. This is an important factor; you must have good wood. You are running just a little on the small size. From a quarter of an inch up to—. I never set a scion over about 9/16. That is just getting into the rough ... It's hard on the tool and rootstocks.
MEMBER: Do you wax the graft?
MEMBER: By all means you use the proper wax.
MEMBER: Did you ever try not to?
MR. GERARDI: Yes, if favorable weather permits. I use this Acme compound. Last season, it was a little stiff and I mixed a little oil and it cut my rubber bands too quick. That brush wax is about as good as you can get, but customers come in and I am called away and someone is always interfering with the work. I was trying to get a wax that I could just drop and it would be ready when I picked it up again. It is beginning to be an assembly line production. You can go faster if you have a helper or two to do the tying and waxing.
MEMBER: I have a rather crude scion storage method. I have dug out in a hill a reservoir that I keep ice in. If you could keep it at 32 to 40 degrees from the time it is cut in February, or the first part of March and then store it in this until the grafting time, it will keep readily.
MEMBER: In California I built a little house and there was room enough to put in at least 40 bushel boxes, 900 pounds of ice and I packed grafting wood in boxes and kept it until July.
MEMBER: The ice keeps up the humidity.
MEMBER: There are a lot of successful methods. It is what is available for you.
MR. WILKINSON: I have had very little experience in propagation of chestnuts. Mine has been limited. I shoulder my scions. I like to shoulder. My percentage of take varies with the conditions, sometimes it's fairly good and sometimes not so good. I have a specimen union of two inches in diameter and you can see what a nice union it makes. Ordinarily I have had very good success with chestnut grafting.
DR. McKAY: We have done some work on budding chestnuts but it hasn't been successful. We have had indefinite results. As Mr. Stoke says, grafting is so much more simple. We realize more work should be done on budding. We simply do our propagating the way it is easiest. Until the time comes that we have got more information on budding we will go along as we do now. One of the difficulties is that the wood is fluted and it is hard to get a good bud fit. It doesn't make for a good fit. We carried out a little experiment on one year old seedling at the crown. There is a smooth area on the stem as it enters into the root condition. It is a perfectly smooth area and we tried putting sealed buds at that point. We have had good success in putting those kinds of buds in at the time when you would ordinarily bud fruits, in the fall, where growth conditions are still good. Another year we did that same work and we didn't succeed so well. So we don't know exactly what we did wrong. In order to keep a set from those buds we don't know just what the conditions should be.
MR. O'ROURKE: To summarize then, the two successful methods are the greenhouse method and the field method used by Mr. Gerardi.
MR. STOKE: I mostly use a plain splice. The cut is about four times as long as scion diameter, if it is on a stock of the same size. It is the best method. I use also a modified cleft graft with a little trimming. Mr. Jones brought out that modified cleft graft and I have made a little change. Here is the stock, and a modified cleft graft is a side graft with the stock top cut off. You cut in at an angle far enough and you put your scion in here and there is your modified cleft graft. You get contact on all four lines. It takes experience and judgment. You cut your scion wedge and then make your understock cut and you will seldom make a mistake after you get experience. That is a side graft and a modified cleft graft. That makes a flexible portion here and you get a fit on both sides. But with the ordinary cleft graft, if you go to the end of your stock you still have a split and not a perfect fit.
MEMBER: Would you explain that? If your scion is not the same size it might over lap or ... how do you handle that?
MR. STOKE: If the scion is undersized, you don't cut so deep. Sometimes the stock is a little oversize. You simply cut less deep in your stock. If you have a large stock and small scion I'd make a bark graft.
MEMBER: I should like to bring up one point. That is produce more nut trees and do it cheaper. It seems to lie between Mr. Gerardi and Mr. Bernath. Mr. Gerardi can set between six and seven hundred per day, and tie them himself, and Mr. Bernath will graft between seven hundred and a thousand a day with someone else doing the tying.
MR. CHASE: We have tried all these grafting methods with varying degrees of success. Our propagation experiments at Norris have been directed at the development of more economic methods.
Conifer grafts are often placed in a grafting case for rapid callusing. This year we tried some black walnut grafts and found that they callused in 10 to 14 days when placed in a grafting case. These were bench grafted on piece roots, using modified cleft and side grafts. Later we tried chestnut with excellent results. Then we made more chestnut grafts, wrapped them in damp moss and placed them in a lab oven with a temperature of approximately 75 degrees. These callused rapidly and were planted immediately in the nursery. They made good growth.
We think that some adaptation of this method has possibilities in our region. Often our chestnut grafts are damaged by late spring frosts. If we can bench graft, callus, and then hold the grafts until favorable weather, frost damage will be eliminated. It may be possible to handle black walnut in some similar fashion. Then we would be dealing only with successful grafts. A cold frame provided with heating cable should be adequate.
Factors Affecting Nut Tree Propagation
F. L. O'Rourke, Department of Horticulture, Michigan State College
Propagation of nut trees is primarily involved with the problems affecting the perpetuation of selected clones by vegetative means. It has been indicated by Morris (14), Reed (18), and others that trees produced from seed are of inferior value for nut production. Seed propagation, however, must be practiced to produce the necessary rootstocks upon which the selected varieties are budded or grafted.