Eight Persian walnut seedlings in the same plantation, set out in 1926, have made poor to fair growth. They have given very few nuts until this year (1947) when two of them are showing a very fair crop.

About 1928 twenty Japanese walnuts and hybrids with the butternut, and about the same number of Persian walnut seedlings, which have been brought in by the late Professor Jas. A. Neilson, were transplanted to the permanent fruiting positions. The Japanese walnuts and hybrids were worthless and so were discarded. The Persian walnuts, however, seemed to be of more value, several are quite nice nuts and one, at least, looks to be worthy of increase for further trial or limited distribution. This seedling (field number 13R3T14) has made very fair growth and has shown only slight winter injury. For the last five or six years it has given moderately good yields of very nice looking nuts. The nuts are large, rather long and oval, resembling somewhat the Franquette. The shell is smooth and moderately thick, well sealed but easy to crack. Usually they are quite well filled and the kernel is mild in flavour and of nice quality.

Another Persian walnut, set out about the same time, is the McDermid. The original tree was found on the property of a Mr. McDermid at St. Catharines, Out. One grafted tree and four seedlings were planted on the Station grounds. They grew well and showed very little killing back and for several years gave quite nice crops of nuts, but of recent years the yield has been rather small. The nut is blunt-oval in shape and of good size with a fairly hard shell which is well sealed but not any too easy to open. The quality is fairly good but the pellicle is rather strong flavoured.

The year 1936 may be considered the high water mark in nut planting at the Station. A variety block of filberts was set out that year and fifty one-year-old Persian walnut seedlings (Carpathian strain) were planted in a nursery row, and in permanent location in 1937. The filbert planting consisted of from three to nine bushes each of twelve varieties, including Aveline (white), Barcelona, Bixby, Bolwyller, Buchanan, Cosford, Daviana, Du Chilly, Medium Long, Red Lambert (?) and Jones hybrid. These were planted in a compact block, 18 feet apart each way on the square. A lesser distance no doubt would be sufficient for upright growing sorts like Du Chilly but some of the more spreading kinds can use the greater distance.

Most of these filberts started to yield a few nuts at five to seven years from planting and at nine or ten years were giving good crops. Yields have fluctuated considerably from year to year, and also between varieties and different bushes of the same variety. Yields obtained from individual ten-year-old bushes and size of nut are given in the following table.

Quarts[2] Pints, nuts Size of nut Name (with husks) (without husks) No. per pint

Barcelona 11 8 101 Bixby (1) 11 9 130 Bixby (2) 22 12 148 Daviana (1) 10 6 94 Daviana (2) 11 7 90 Du Chilly (1) 20 11 93 Du Chilly (2) 17 12 92 Medium Long 11 8 115

[Footnote 2: Canadian measure.]

Higher yields have undoubtedly been obtained from other plantations and from other individual bushes and certainly lower yields, also, may be expected. Those given above are for 1946 from the best ten-year-old bushes in a plantation of forty plants.

Yield and size of nut while of major importance are not the only criteria for appraising the value of a nut variety. In filberts, such points as ease of husking, amount of fibre and, of course, quality must be considered. Also, as in other nuts, thickness of shell and proportions of kernel to shell are quite important. Vigour and hardiness of bush and hardiness of flower, male and female, are assumed, as without these high yields are not to be expected.

Most of the filbert varieties in bearing at the Horticultural Experiment Station with a few of their outstanding qualities are noted below.

Barcelona has a rather thick shell and too much fibre. It matures early, first week of September, and the nuts drop out of the husk fairly readily. The plant is strong and vigorous and somewhat spreading in habit of growth. It appears to be hardy.

Du Chilly is not always hardy and it is difficult to husk. Some bushes of this variety have given quite low yields.

Medium Long is a useful nut. It is not as large as the former two, but it fills well and there is very little fibre; also the shell is thin. It ripens somewhat later than Barcelona and is easy to husk.

Bixby is of medium size, somewhat pointed with a medium thick shell but almost no fibre. It is late in maturing, first week of October, and does not husk readily.

Daviana is a large, attractive nut with a moderately thin shell and has very little fibre. The quality is good. The nuts are mostly borne singly but with some pairs and they are apt to cling to the husk.

Cosford is a very nice nut. It is similar to Medium Long, somewhat smaller and of good appearance. It has a thin shell and is of good quality. It ripens early and separates readily from the husk. Perhaps not always hardy.

Bolwyller is hardy, yields moderately well and has nice quality.

Buchanan, much like Bixby, but a more vigorous grower. Rather difficult to pick. The nut has good quality and very little fibre.

Italian Red, one of the best but not hardy.

The filbert plantings have been added to from time to time. In 1942, 200 open-pollinated seedlings of the hardy seedling (3R1AT 10, 11, 12—1922 planting) were set out and are now (1947) beginning to bear a few nuts. The main purpose of growing these seedlings is to find a larger nut of good quality with the vigour and hardiness of the female parent.

In 1944 a bush each of Beethe, Buchanan, Luisen and Volkugel varieties were set out, also bushes of the following hybrids:

Rush x White Aveline No. 21

Rush x Kentish Cob No. 110 and 111

Rush x Barcelona No. 157 and 159

Rush x Bolwyller No. 200

Rush x Red Lambert No. 394 and 398

Rush x Du Chilly No. 485 and 555

Rush x Daviana No. 529 and 521

This material was supplied by the New York State Agricultural Experiment Station for test purposes. So far none of these has come into bearing.

The seedling Carpathian walnuts (1937 planting) are nearly all bearing a few nuts. Some began in 1943 while other bore nothing until several years later. One tree in 1946 gave six pints of nuts, without the husks, another four pints and several two pints, but most of them much less. As in other seedling trees there is much variation in this lot of walnuts. They vary considerably in habit of growth and vigour, also in nut characteristics. They have shown little or no winter injury. It is too early yet to pass judgment on these seedlings. Undoubtedly many of them are worthless, others are on the border line, and a few may be better than seedlings already growing in the Niagara fruit belt. It is possible that some may have sufficient hardiness for planting in the less favoured sections of Ontario.

Other types of nuts growing at the Horticultural Experiment Station are of general interest. The chestnuts and most of the pecans are very young and so are not bearing. Several hickories, Carya ovata and C. laciniosa, and Japanese walnuts bear some nuts occasionally. The Persian walnut x black walnut hybrids bear a few nuts sometimes but are worthless; the trees however, are nice as ornamentals. The Japanese walnut x butternut hybrids usually have a nice crop but the nuts are of questionable value. The trees are nice ornamentals although subject to wind injury.

Several seedling Chinese chestnuts were topworked to selected Chinese chestnuts, grafts of which were obtained from the Division of Forest Pathology of the U. S. Department of Agriculture. Unfortunately these were all destroyed at the result of construction work.

In addition to plantings made at this Station, nuts and nut seedlings have been distributed to people who wished to grow a few nut trees on their own places.

Cultural practices have been very simple at the Station. After planting, the trees were cultivated for a year or two, then the space between sown to grass and clover and the space just around the trees was mulched with manure, hay, etc. The grass is cut several times a year and placed around the trees as additional mulch. Small quantities of a good commercial fertilizer such as 4-8-10 have been applied occasionally and some nitrogen also has been used.

Pruning has been reduced to a minimum, a light thinning out of branches being given as required. Very little attempt has been made to keep filberts to a single stem, but the walnuts have been kept to a single low-headed trunk.

There has been a marked increase in interest in the planting of nut trees in Ontario since the first plantings were made at the Station. These Station plantings serve to demonstrate in a small way that nut trees can be grown in the Niagara fruit belt of Ontario. The feasibilty, however, of growing nut crops in a commercial way, even in this district, is still open to question, although it is felt that farmers and others should be encouraged to plant a few nut trees on their property both for the sake of the nuts and because of the ornamental nature of the trees.



Soil Management for Nut Plantations in Ontario

J. R. van HAARLEM, Horticultural Experiment Station, Vineland Station, Ontario

Fruitgrowers with high priced land, such as we have in the Niagara Peninsula, are not much interested in using such land for a crop not yet proven commercially sound. Plantings, whether large or small, are likely to be made on low-priced marginal land needing good care. It is doubtful if these locations are best suited to proper nut culture since most nut trees are deep rooted with extensive root systems requiring the best soils.

At the Vineland Station we have three plantations made up of 110 walnuts, 240 filberts, 14 chestnuts and 6 pecans. These comprise named varieties and seedlings of black, Carpathian, and other Persian walnuts, filberts, chestnuts and pecans.

During the first years of the life of these plantations we maintained a clean cultivation program during the spring and early summer followed by the planting of a green-manure crop about July 1st each year. Such crops as buckwheat, millet, rye, and weeds, have been used on occasion. We soon found that the treatment was not good enough for the trees and we then changed to a grass sod with mulch around each tree within the spread of the branches. Since this sod-mulch treatment was applied the trees have done very much better, making fine growth and maintaining a large leaf area of good color. This treatment is fairly representative of the many trees planted in dooryards under sod conditions, where the grass is cut and left on top.

Most of our Ontario soils are deficient in organic matter and, depending on location, deficient in phosphate or potash, or both together. The mineral deficiency should first be corrected by liberal applications of the required fertilizer before placing the plantations in sod, in fact it would pay to do this several years before setting out the trees, growing alfalfa on this land and returning all the hay back into the soil. For plantations already set out these minerals could be placed in a furrow cut just under the outer spread of the branches. Our soils have a high fixation factor for phosphate and potash and we have found that the best practice is to place the fertilizer under the surface either with a deep-placement machine or as outlined above.

After the plantation is in sod an application of 500 to 1,000 lbs. of a 4-8-10 fertilizer every fifth year should take care of the mineral requirements. However, our experience with fruit in general where planted in sod is that not sufficient care is taken to keep the trees well supplied with nitrogen, many growers laboring under the mistaken idea that just the sod is sufficient. Liberal applications of either manure or nitrate in the spring is necessary to make sure that the tree gets its required nitrogen and not just the sod alone. Mineral fertilizers should be applied in the late fall, for under our conditions fixation of phosphate and potash is considerably less at that time. The plantation may be seeded down in the early spring but mulch should not be added until late fall. Applying the mulch in late fall will allow the material to fill up with water from the fall rains and winter snows, and so prevent the serious withholding of water from the trees during dry spells in the summer, because the light summer rains are seldom sufficient to soak through the dry mulch material. We have had several instances where a summer-applied mulch has seriously robbed the tree of needed moisture during dry weather. Do not look for immediate improvement from sod-mulch, it will take at least two years to become well established. Improvement should begin to show up the second year after applying.

We sometimes see a chlorotic condition of the foliage, different from the pale yellow foliage due to nitrogen deficiency, which occurs on marginal or shallow soil and often where the soil remains too moist, as along a water course or low spot. We frequently see this same trouble on grape foliage in such locations. This is probably due to a lack of sufficient iron intake caused by a deficiency of manganese. It can be cured by either spraying with a 1% solution of magananese sulphate or applying the dry salt under the spread of the branches. The spraying method seems to give better and faster results.

It has been reported from British Columbia that some die-back is due to deficiency of boron. Perhaps some of the die-back we see on nut trees during the summer is due to this cause and not all to winter injury. The very erratic results from ground application of borax would indicate that borax should be incorporated with one of the regular sprays as a 1% mixture.

Our conclusions therefore are that nut plantations should be placed in sod as soon as possible and a mulch established the fall of the year the grass is sown. Each year cut the grass and draw in around the tree to supplement the mulch. If not enough material is gathered in this way it can be supplemented by straw or old hay. Manure or nitrate should be applied each spring and trace elements where needed can be incorporated in the regular spray program.

* * * * *

Discussion after J. R. van Haarlem's paper.

Dr. MacDaniels: "I realize that there are more trees which are starving to death than are being overfed."

Silvis: "Do you recommend that freshly cut hay be used as mulch?"

Van Haarlem: "Any crop refuse can be used as mulch. Anything that will rot down. The pH of the soil should be 6.2 to 6.5."

O'Rourke: "Would you use clean cultivation for the first year?"

Van Haarlem: "There is nothing against it. We use sod mulch at Vineland. The reason that our growers are not growing nut plantations is that good land, that is good soil, sells for $1,000 per acre. Nut trees grown on poor land, cheap land, do not produce."

McCollum: "I am surprised that rain would not go through loose straw and will go through old straw. Where does the rain go when it falls on the loose straw?"

Van Haarlem: "It is absorbed before it gets through the straw. Dry mulch should be 18 inches deep."

Member: "How would you prevent erosion on rolling land?"

Van Haarlem: "Plant on the contour."

Dr. Crane: "How often do you renew mulch under trees?"

Van Haarlem: "After first application additional may be needed but after that enough is grown under trees which when cut and raked will suffice."



Report from Southern Ontario

ALEX TROUP, Jordan Station, Ontario

Here in southern Ontario we find that most of the northern nuts do well in most seasons. Among black walnuts the Thomas, Ohio, and many others do well. The Thomas does not always fill. The Ohio seems to be the favorite among Persian (English) walnuts. Franquette, Broadview and a few others are satisfactory but sometimes do not fill well. Of Japanese heartnut walnuts nearly all do well. The Mitchell, Stranger, Bates and others are satisfactory.

All the shagbarks and shellbarks are doing well, although only the young shagbarks are bearing, and then only lightly.

Chestnuts have done well at times but some trees have been killed by the blight. We have Japanese, Chinese and some other seedlings. They are sometimes winter injured.

Filberts are satisfactory and usually bear well. We have Barcelona, Du Chilly, Troup, White Aveline, Italian Red, Kentish Cob, Daviana, Mosier, Guy Smith, Nonpariel and Brixnut. The Barcelona drops nearly free of the husk and is a fine nut. Most are of this variety. We do not have hazels.

Pecans will grow and bear but do not fill.



Nut Trees Hardy at Aldershot, Ontario, Canada

O. FILMAN, Aldershot

During the past nine or ten years I have planted a few trees of some of the better known varieties of northern nut species, some of them chosen from the lists of promising selections in the annual reports of the Northern Nut Growers Association, some on the recommendation of reliable nut nurserymen. These trees have been planted here and there in various locations where space permitted on a small fruit and vegetable farm, not in orchard form nor in a solid nut tree planting.

Editor's Note: Anyone reading this paper should remember that it applies to an area of intensive growth of peaches, pears, and other fruits in a bit of Canadian land west of Niagara Falls and protected spring and fall from extremes of temperatures by Lake Ontario on the north and Lake Erie on the south. The paper by H. L. Crane in this report should be read in connection with it.

Aldershot is a fruit and vegetable growing district, about six miles from Hamilton, below the escarpment, on the Toronto-Hamilton lake shore highway. This district is almost at the western tip of Lake Ontario and is more or less a continuation of the Niagara fruit belt which borders the lake. Consequently the climate is not so severe as that of localities situated a few miles farther from the lake and above the Niagara escarpment at higher altitudes. Winter temperatures seldom go much below zero, although, in occasional seasons, temperatures of-20 degrees F., and sometimes even somewhat lower, are experienced.

The soil is a deep, well-drained, light sandy loam, known as Fox sandy loam, considered a good fruit and vegetable soil, if organic matter and fertility are maintained with manure, fertilizers and green manure crops.

Nut trees, which I have planted, include Chinese chestnut, heart nut, filbert, hickories, butternut, Persian walnut, a few black walnut seedlings and two seedling pecans.

Chestnuts. The native chestnut grew in the woods of this locality before the blight reached it. I have tried eight varieties of Oriental chestnuts, and I have trees surviving of five: Abundance, Hobson, Carr, Zimmerman, and one of Mr. Carroll D. Bush's called Chinese Sweet No. 3. They all came through a temperature of about-20 degrees, early in 1943 (with the exception of Zimmerman which was planted later) without showing any sign of killing back or other visible injury. Unfortunately, I have kept no records of crops but expect to do so.

Abundance. One bearing tree, purchased from Mr. Bush of Oregon, and planted in the spring of 1938. Bore a few burs in 1941. Bore a crop in 1944, missed 1945, a good crop in 1946. It is bearing what appears to me to be quite a heavy crop this year, 1947. Blossoms in July. Bears a good-size, attractive nut, which falls free from the bur, ripening in early October. Abundance has made the best growth of any of the varieties and appears the most promising.

Hobson. Two trees, one, planted in 1940, bore its first crop in 1946; the other, planted in 1943, not yet bearing. Has been a little disappointing, in view of the very favourable reports of its performance in more southern locations in the United States. Probably it is a little too far north of its natural environment. In some seasons it has made rather good growth, but not as vigorous as that of Abundance. It bore a fair crop in 1946, however, of attractive nuts of about the same size as Abundance. It ripened in late October about two weeks later than Abundance. These nuts germinated well this spring when planted in pots in the greenhouse.

Carr. One tree surviving, planted in 1940. Two others, planted in 1943, have died, but I do not believe that winter injury was the cause of their death. Has grown slowly, bearing in 1944 and 1946. The nut is much smaller than that produced by the same variety at more southern latitudes, judging from descriptions of it which I have read. The nut is much smaller than that of Hobson, as grown here. This small tree bore a tremendous crop in 1946, more than I thought any tree of its size could support. The tree was literally covered with burs. The nuts were very small, not larger than a small native chestnut. They ripened early, beginning to drop from the burs by September 25th. I stratified most of the nuts in pots of soil and planted 206 nuts from this little tree, which is only about seven feet high and not at all spreading. Germination was good.

Zimmerman. One small tree planted spring of 1945. Not bearing yet. Is not growing fast but appears healthy with good foliage.

Chinese Sweet No. 3. Purchased from Mr. Bush in 1938. Planted at the same time as Abundance, which Mr. Bush at that time called Chinese Sweet No. 1. He later named No. 1 Abundance, but did not consider No. 3 worthy of naming. Has grown well, but has borne very few nuts. Mr. Bush discarded it for the same fault. [See comment following.—Ed.]

I have also tried and lost the following varieties: Connecticut Yankee, Austin Japanese and Stoke hybrid.

I have quite a number of young seedlings of Abundance, Carr and a few of Hobson, from seed produced on my own trees, some of which I hope to allow to bear in order to see if anything promising shows up among them. The Abundance seedlings seem to inherit the superior vigour of their female parent.

Heartnuts. The Japanese walnut grows vigorously. I have planted a few of Mr. J. U. Gellatly's varieties, as well as the Wright heartnut. All of the ones planted seem perfectly hardy and at home. I have only one tree of each variety.

O.K. From J. U. Gellatly, planted in 1942. Transplanted 1944. Bore its first nuts, one cluster, in 1946. Cracking and extraction of kernel were excellent. The flavour was fine. Size of nut about medium.

Okanda. From J. U. Gellatly, 1942. Said by Mr. Gellatly to be a hybrid between heartnut and native butternut. Tree vigorous. Nut has a smooth shell like a heartnut. Cracking and extraction good. Flavour excellent. Nut about size and shape of a medium-sized heartnut. Bore its first crop in 1946 and is repeating this year with a fair crop.

Crofter. From J. U. Gellatly, 1942. Also said by Mr. Gellatly to be a hybrid between heartnut and butternut. Tree vigorous. Bore its first crop in 1946 and has a few nuts this year. The nut has a comparatively smooth shell like a heartnut, is somewhat larger than that of Okanda but does not crack as well, or rather the kernel does not come out of the cavity nearly so well as that of Okanda. Flavour fine.

Canoka. From J. U. Gellatly, 1944. A pure heartnut. Tree very vigorous. Bearing its first crop this year, several clusters.

Slioka. A new heartnut from Mr. Gellatly, planted in 1945. Tree growth is vigorous. Is bearing one nut, its first, this year.

Wright. From Benton and Smith nurseries 1946. Seems to be hardy. Tree growth has not been very strong but appears healthy.

New, un-named heartnut. From J. U. Gellatly, planted in the spring of 1944. A new selection which Mr. Gellatly has not named. The tree has grown vigorously and it is bearing its first crop of several clusters of nuts.

Butternuts. I have only one grafted butternut tree, a Crax-ezy, from the Michigan Nut Nurseries in 1940, transplanted in 1942. The tree has been hardy and healthy but has not grown very vigorously. It is bearing its first crop this year.

I had one tree of the Sherwood butternut, planted in 1938, which died last winter as a result, I believe, of a heavy infestation of oyster shell scale which I did not control soon enough. Sherwood bore early and heavily. The nut was extremely large but did not crack at all well.

Persian walnut. Only one grafted tree, a Broadview, from Mr. Gellatly, planted in 1942, transplanted in 1944. Has been hardy, but has just begun to make really good growth, this year. Has not borne.

Filberts. I have planted four of Mr. Gellatly's varieties, namely Craig, Brag, Comet and Holder, as well as Barcelona, Cosford, Medium Long and Buchanan. Craig and Brag are the only ones which have borne. Trees of those varieties planted in 1942 bore their first crop in 1946. They have very few nuts on them this year. All varieties seem to be winter-hardy in the wood. Craig, Brag and Comet, the only ones which have borne staminate flowers do not seem too hardy in the catkins however. Nearly all were killed, last winter, although the temperature scarcely went as low as zero. Mr. Gellatly states that their catkins survive much lower temperatures than that in the west. Some other factor than low temperature probably is accountable. (See paper by H. L. Crane in this report.—Ed.)

Cosford, Medium Long and Buchanan were planted in the fall of 1946, and hence it is too early to have any information on their hardiness. They survived their first winter in good condition and have grown vigorously this summer.

Hickories. Only three grafted trees surviving.

Pleas hybrid. One tree, planted in 1938, has been perfectly hardy, having come through several severe winters without any sign of injury. It has made good growth and has developed into a fine shade tree for the lawn but has not borne. It has had many staminate catkins for several years.

Barnes. One small tree, planted in the spring of 1946, has made slow but healthy growth and appears to be hardy thus far.

Miller. One tree, planted in 1946, is still living but very weak.

In addition to these named varieties I have a number of seedling black walnuts, butternuts and heartnuts, which I hope to topwork to named varieties; also two seedling pecans which are making surprisingly good, thrifty growth. The pecan seedlings have been quite hardy.

* * * * *

Discussion after Mr. Filman's paper.

Stoke: "Hobson is not as large as Abundance. Abundance is always larger than Hobson. Carr always produced better nuts than Hobson. Mr. Filman finds that Carr has very small nuts. I am surprised to see a reversal of performance between Ontario and Virginia."

McDaniel: "Mr. Bush now reports that his No. 3 chestnut has borne better crops recently. Abundance has not survived in TVA tests at Norris."



Report from Echo Valley, 1947

GEORGE HEBDEN CORSAN, Islington, Ontario

The Northern Nut Growers Association visited Echo Valley, Islington, Ontario, September 5th on the field trip following their annual convention at Guelph. Some 15 species of nuts and nearly 400 varieties are growing there. The filberts drew a lot of attention, as the most of them were seedlings and quite large, some larger than the largest Oregon varieties. The seeds planted were: Italian Red. Du Chilly, Giant de Halle, Brixnut, Bollwyller, Cosford, Daviana, and Jones No. 1 Hybrid. The policy followed has been not to discard a plant because it bears small nuts or no nuts at all, because such trees may bear hardy catkins that live through the winter. The female blossoms of filberts are very hardy but many male blossoms may be killed during cold winters.

Years ago the Dominion Department of Agriculture declared that filberts, chestnuts and Persian (English) walnuts could not be grown north of Lake Ontario. I would grant that they grow better south of the lake. However, the filbert crop this fall south of the lake was very poor and scanty, whereas mine was large and in fact the largest I ever had. My Winkler and Rush hazelnuts are crowded on the branches. And the same with the English walnuts. My crop on the larger trees could not be better. The Thomas black walnut, as well as other black walnuts, Jap heartnuts, hybrid butternut x Japanese heartnut cross, chestnuts and hickories are very large.

Hicans and northern pecans do not develop north of Lake Ontario. Down in the very southwest corner of Ontario, north of Lake Erie, some small pecans have cropped well on trees. As a curiosity pecan trees are quite hardy here, but we lack length of season to mature the nuts properly. No Weiker hickory hybrid crops and ripens well here. This nut is one of the very few crosses between shellbark and shagbark hickories, (Carya laciniosa) western and (Carya ovata) eastern, hickories.

I have some crosses between the Chinese and Japanese chestnuts that I am watching. I have one European x American cross chestnut, the Gibbons, and one native (Castanea dentata) that have escaped the blight. So far this year I have found only one blighted chestnut limb and I promptly cut it off and tarred the cut well.

At least I have persimmons hardy enough to stand the winters north of Lake Ontario, but I am not sure about the pawpaw. This fruit seems to require shade from the winter's sun.

Many but not all of the Crath importations of Persian walnuts from the Carpathians are hardy and much more so than the Pomeroy varieties. Even the Broadview is not hardy as many of the Crath varieties. Rev. Crath did an immense service to us by his importations which far exceeded our highest expectations. I have here nearly half a hundred varieties of Juglans regia that are doing well, especially the three Rumanian giants that ripen so well here.

List of Some of the Larger and More Important Trees at Echo Valley, Islington, Ontario

Black Walnut Stambaugh 1926—1st prize. Thomas from J. F. Jones, late ripener. Troup, cracks out whole in spring. Hepler, from Miss Riehl, a long nut. Elmer Myers, excellent flavor, the thinest shell. Snyder, medium size, large kernel. Tasterite, a small nut, origin New York State. Clark, origin Iowa, very large nut. Gifford, bears very heavy crop every second year, ripens before Thomas.

Persian (English) Walnut David Fairchild, seedling Rumanian giant. Senator Pepper, seedling Rumanian giant. Paul de Kruif, seedling Rumanian giant. Chinese, very hardy, medium size. Broadview, from British Columbia but originally from Russia.

Hickory Neilson, a true shagbark, nut large flat and very thin shell, flavor is wonderful. A big tree on highway 24 not far south of where Alexander Graham Bell perfected the telephone. Hagen, a true shagbark, a fast grower. Hand, a shagbark. Weiker, a shellbark and shagbark cross, a large, heavy bearing nut that ripens here north of Lake Ontario. Excellent flavor, grafted on pecan. Papple, a small good shagbark, cracks out whole. Anthony No. 1 shagbark. Glover, from Miss Riehl.

Heartnut Wright, a good bearer and excellent cracker. Stranger, very heavy bearer, excellent cracker. Gellatly.

Filbert Italian Red, medium long with wide base. Bollwyller, large round. Du Chilly, long smooth. Many seedlings of named varieties.

Chestnut Gibbons, Miss Riehl, hybrid European American. Chinese, test not completed.

Jap Butternut Helmick, from Miss Riehl, 14 cluster, regular bearer, very thin shell, grafted on black walnut.



Report from Beamsville, Ontario

LEVI HOUSSER

About twenty years ago I started to plant nut trees, as I decided nuts were the solution to good health, which I later found was correct. Most of my first trees died. I started gathering nuts all over the country until at last, near my own home, I found a neighbor who had ten trees and two out of the ten were bearing large size nuts of an excellent flavor. I also added filberts to my collection.

About this time I learned of Prof. Neilson, so I went to see him in Guelph. He told me about the Northern Nut Growers Association. I also learned about Mr. Corsan and his work at Islington so I went to see him. He also told me about the Association so I went to the next meeting and joined up. I began to add more varieties to my plantings. My first four acre planting was seeded with oats the second year. All my tress had a nice start. I spent some three hundred dollars that year for grafted nut trees. That second fall I hired a man to watch and stand by each tree as the binder passed. It was impossible for me to be there. The man who cut the oats in his own stubborn way went alone and cut everything as he went, trees and all. My heart was nearly broken! I started again. I bought nuts of good varieties from all over. I decided to make a little nursery this time then plant out after the trees got bigger. Just as I got this started nicely the war came. I also had a fruit farm where I now live besides also planting some grafted stock here. My nursery, seventy-eight miles away on my fifty acres, I had to leave as gas was rationed and I was forced to sell, so remaining there are about one hundred trees which I shall watch. My best trees died but I kept going on planting every year. Today, after all the calamities I had, I have around two hundred trees living.

This year I expect two bushels of heartnuts; about two bushels of filberts; some extra nice ones that ripened early, large and well filled; about two bushels of black walnuts, some very promising. Besides these I have about fifty trees of the Carpathian walnuts from which I have gathered about two quarts of nuts. My oldest tree is ten years old. One I grafted on black walnut stock and it is a very large nut. I gathered five nuts from this. The graft is now five years old. Hundreds of nuts started; nearly all dropped off. Possibly as the tree gets older it will do better as I have planted several other nut trees not far away to help with cross pollination.

I have some good sized butternuts and I gathered about 17 quarts of these so I expect to have enough nuts to supply my daily needs from now on from my own plantings. After twenty years of hard work and with an outlay of at least $1,000, my trees, as they grow up around me, are like children to me. They supply me with food. My nervousness was cured by them and my health has returned.

My worst enemy here with filberts is they start to grow too early, then a frost comes and they are done after a week or two of nice weather. Even though we have this trouble we gathered nearly two bushels from 25 trees which are eight years old.

Our lowest temperature here was 20 below zero a few years ago. My Carpathians did not seem to mind that nor did the heartnuts. From now on I am planning my own little nursery and do my own grafting as well. I top work my young trees that show poor nuts.



Nut Growing in New Hampshire

L. P. LATIMER, Assistant Horticulturist, University of New Hampshire, Durham, New Hampshire

At the present time there are no nuts grown commercially in New Hampshire. Those gathered by the residents of this state for home use or local consumption are comprised almost entirely of butternuts from wild seedling trees and nuts of the native hickory. The butternut is the most highly prized among our native nuts. It grows wild over a large portion of the state. The hickory nuts take second place, probably because of their smaller size and the greater difficulty involved in removing the meat from the shells. Black walnuts are occasionally found but do not seem generally as popular.

Dr. A. F. Yeager of the Horticultural Department of the University of New Hampshire, Durham, New Hampshire, has several times called for specimens of superior butternuts grown in the state. These have been tested for their cracking ability, and size of kernel and ease of removal from the shell in halves or as whole meats. Several very fine specimens have been collected, but progress in the development of these better types has been impeded by the difficulty involved in trying to propagate them vegetatively. The New Hampshire Horticultural Department would gladly welcome any information concerning the propagation of the butternut that would make grafting or budding successful.

The best possibility in developing commercial nut crops in New Hampshire apparently lies first in the use of the hazel or filbert. Although the European filbert has not been very successful, such varieties of the American hazel as Winkler and Rush look promising. The Winkler has borne heavy crops but in a short summer season the nuts do not always mature fully in the fall. Although we have had much less experience with the Rush variety, this does mature earlier in the fall and seems promising. Some of the Jones hybrids have been tested at the Experiment Station in Durham, a few of which have done quite well. Of these Jones hybrids No. 1181, 1154, and 1094 have made quite vigorous growth. Seedling No. 1094 has been outstanding, producing good sized nuts which mature well and shell out easily from the husks. In type and flavor of nut it resembles the European hazel quite strongly under our conditions.

So far, none of the chestnuts, including the Chinese species, have shown great enough resistance to chestnut blight to warrant their recommendation. We still hope that we may discover a good chestnut for this section. The hardy Persian or English walnuts have not been tested long enough to warrant any conclusion as to their promise for New Hampshire; one difficulty will probably lie in the fact that the nuts of some do not ripen properly under our cool, short summer conditions.

Mr. Matthew Lahti of Wolfeboro, New Hampshire, has been experimenting with various species and varieties of nuts for that section. His location on the shore of Lake Winnipesaukee undoubtedly presents a more favorable site for growing certain types of nut plants than exists here in Durham, or most other parts of New Hampshire. At the present moment I have on my desk a parcel received from Mr. Lahti containing some fine specimens of one of the hardy Persian walnuts which he is growing in Wolfeboro. The unusually warm and dry late summer and fall of this year have favored the maturity of this walnut. (For a detailed description of Mr. Lahti's experience with nut varieties, please refer to his paper printed below.)



Nut Notes from New Hampshire

MATTHEW LAHTI

Not being able to attend the annual convention I thought possibly some of the members might be interested in the following random notes of an amateur nut grower.

My place is in Wolfeboro, N. H., which is situated in the eastern end of Lake Winnepesaukee, 43 degrees, 35 minutes north latitude; elevation above sea level, 687'. The elevation of the lake is 504'. Wolfeboro is just about at the northern fringe of the climate where peaches will ripen, that is during favorable years in favored locations. Improved varieties of field corn will ripen during favorable seasons. It also happens to be the northern fringe of the American chestnut, in favored location. I have discovered a number of saplings that are still alive. As a matter of fact, three or four years ago I was fortunate in finding some ripened nuts, but the trees that bore those nuts have since died of the blight. While a certain variety of old fashioned sweet cherry will live and bear fruit, some of the recent improved varieties will not live. Every one that I have planted was winter-killed. The Montmorency cherry, however, does well. It is also the northern limit of the pignut. Butternuts do very well.

DDT Dust versus Butternut Curculio

I was prompted to write this note by reading Mr. S. H. Graham's article entitled "An Experiment with DDT" appearing on page 101 of the 1945 annual report, in which he states that the butternut curculio did not survive DDT powder.

In the past four or five years the butternut curculio (identified as such by Prof. Conklin of the University of N. H.) has all but ruined my Crath Persian walnuts and heartnuts, so, acting on the basis of Mr. Graham's experiment, I had my trees dusted early in the morning when the dew was on the leaves, using a 10% DDT powder, the first time about May 30 and again two weeks later, and I am happy to say that this dusting has been very effective. I have been unable to find any sign of curculio injury this year, although I have seen it nearby on some native butternut trees.

My Gellatly heartnut was riddled by the curculio last year. This year, when the dusting was done, this tree was overlooked, so I undertook to dust it myself, and not realizing that the Niagara duster which I used was set in the closed position, I dusted the tree with considerable effort. In spite of the small amount of dust that came out, it proved sufficient to keep the curculios away or else to kill them so that there is no sign of any damage at this writing.

Persian Walnuts

In the spring of 1938 I planted a number of Crath Persian walnut seedlings. Out of possibly eight or ten, only two survive. (I gave each one about three years, and if it showed serious winter injury, I pulled it up.) I was pleasantly surprised the other day to discover that one of them has borne a single nut this year. This particular tree is at least 300' from any other Persian walnut, so it looks as if it were self-fertile. It now remains to be seen whether or not the nut will ripen.

In the spring of 1940, I planted a Broadview Persian walnut graft on black walnut stock, and this tree is bearing for the first time with eighteen nuts showing. Three or four years ago this Broadview suffered some winter damage by a split trunk and split lower branch. I painted over the cracks with gasket cement, and they are now healed. The Broadview has also shown some winter-kill of terminal twigs, but not enough to affect its bearing this year. There has been no splitting of the trunks or branches of the two surviving Crath Persian walnut trees and no winter injury to terminal twigs. The Crath walnut trees are now 18" in circumference a foot from the ground and about 12 to 15' tall. The Broadview on the black walnut stock has a circumference of 16" above the graft and 15-1/4" below the graft, tending to show that the Broadview grows faster than the black walnut.

It is interesting to note that the Broadview blooms a week or ten days later than the Crath Persian walnut, and at the same time as the native butternut.

Black Walnuts

I have planted a few Thomas black walnut seedlings, two grafts, and a Tasterite black walnut graft. A Thomas black walnut graft has borne nuts in three different years, including this year. The graft was sent out in the spring of 1939, and the seedlings were set out in the spring of 1940. The seedlings have not yet borne. The Thomas black walnut graft last bore three years ago, when the nuts on the whole ripened and were well filled. We had a very cold spring in 1945, so much so that apples were almost a total failure.

I also planted a Tasterite black walnut in the spring of 1939, and this is the first year that it has borne any nuts. It remains to be seen whether they will be filled out or not. There is, however, an important difference between the Thomas and the Tasterite, which are growing only 50' apart, namely that the Thomas suffers from winter injury to the terminal twigs each year, whereas there has not been any sign of such injury to the Tasterite.

Hickories

I have planted possibly two dozen of a number of varieties of hickories, of which only nine survive to date, the cause being not winter injury but what appears to me to have been improper circulation through the graft union. They would struggle along for three or four years (producing suckers from the root stock which I broke off), and then die. None of these has borne any nuts yet except the Weschcke, which was planted in the fall of 1941, and which is now bearing one nut. This nut is a mystery to me because the tree bore no catkins. There are no hickory trees within thirty miles of the vicinity to my knowledge, and the nearest pignut tree is perhaps three-quarters of a mile distant, in a direction against the prevailing winds, the intervening space being forest. Could it be possible that the Weschcke hickory was pollinated by a butternut or the Broadview Persian walnut? A big butternut tree stands within 60' and the Broadview is situated about 150' distant.

Heartnuts

I have tried a number of heartnuts, including the Gellatly and the Wright. Only a single Gellatly survives. Here again the cause was not winter injury so much as either the butternut curculio or other causes. The Gellatly, while suffering some terminal twig winter injury and deer damage by rubbing of horns, has borne and ripened nuts.

Filberts and Hazelnuts

I planted a number of Winkler hazels in the fall of 1940, and this is the second year of bearing. The nuts hardly have time to ripen in our climate and a good many of the catkins get winter-killed.

In the spring of 1939 I planted a number of filbert seeds received from Mr. Slate such as No. 128 Rush Barcelona; Medium Long; and Red Lambert. These are bearing for the first time this year, and judging from the size of the nuts now, it looks as if they will mature. Many of the catkins were winter-killed.

Bixby and Buchanan planted in the spring of 1939: While the plants did very well, most of the catkins invariably were winter-killed, so I was obliged to pull them up.

I have a feeling that filberts would do better here if it were not for the very cold winds that blow off the lake in winter, killing most of the catkins.

I discovered a wild hazel in Lexington, Mass., (which town is located in a so-called cold air pocket) the nuts of which are almost equal to the Winkler. I have transplanted some of these to Wolfeboro and shall know more about them later. I also discovered some wild hazels in northeastern Maine, between Lincoln and Vanceboro on the border of New Brunswick, Canada, which two weeks ago had good sized, well filled nuts on them. I have also transplanted some of these to Wolfeboro.

In closing I should like to thank all officers, committee members, and others who are responsible for the annual report. To those of us who do not get to the conventions very often, the report is the Northern Nut Growers Association, and a source of very valuable and interesting information, especially to an amateur like myself.



A Simplified Schedule for Judging Black Walnut Varieties

L. H. MacDANIELS and S. S. ATWOOD, Cornell University

All its members would agree that the Northern Nut Growers Association should have an officially accepted schedule for judging black walnuts and the other kinds of nuts with which it is concerned. Some yardstick is needed to serve as a basis for the comparison of varieties which the members of the Association will use. Persons familiar with nut varieties are freqeuntly asked to answer questions about the best varieties to plant. Of course there is no simple answer to such a question as many factors besides the nuts themselves determine the value of a variety. The quality and value of the nuts are, however, the most important initial consideration in selecting a variety on its merit and there should be some objective test adopted to aid in evaluating nut samples.

During the many years that the Northern Nut Growers Association has been operating more than a hundred and fifty varieties of black walnuts have been named. Yet at the present time we are not certain which are the better varieties except in a very general way. There is no widely accepted judging schedule being used as is evident in the tables published by Seward Berhow in his paper in the 1945 Proceedings (2). In these tables scores are given but these come from several sources and are not comparable and hence are of little value in making comparisons.

There have been many schedules for judging black walnuts presented in the past. One of the first was proposed by the late Willard G. Bixby (3, 4). This was complicated and never came into general use although the testing done by Mr. Bixby was a valuable contribution to our knowledge of varieties. The late N. F. Drake tested many varieties through the years according to a schedule of his own devising (5, 6). Professor Drake's schedule was related to his concept of a perfect walnut and the various values were related to this on a percentage basis. This schedule never had wider acceptance, chiefly because it was too complicated and required too much figuring.

Mr. C. A. Reed has probably tested more varieties of nuts and is more familiar with varieties than any other person but he does not have a definite scoring schedule. Kline and Chase (7) summarized results of the testing work that had been done and Kline (8) compared varieties according to a system which he devised in which they were rated in terms of return per hour of labor spent in cracking and extracting the kernels. Mr. C. C. Lounsberry has proposed a method of scoring which was related to kernel cavity measurement (9).

In 1935, a Committee on Varieties and Standards endeavored to formulate a working schedule that would be adopted as official. This committee set up a score that represented the best thinking of the group at that time (1). Twenty-five nut samples were used. The score was the sum of the weight of an individual nut in grams plus twice the per cent kernel of the weight of the nuts recovered in the first crack plus the total percentage of kernel plus 1/10 of a point for each quarter kernel recovered. Penalties were proposed for shrunken kernels and empty nuts. Through the years a large number of samples have been tested according to this scoring schedule (11). In 1943, MacDaniels and Wilde (12) summarized the previous work done, added many tests and evaluated the scoring system. This was not considered to be altogether satisfactory. In the first place, it was somewhat cumbersome and had never been adopted by the Association nor had it been used much by others. The figuring of percentages and penalties made a score too involved for wide aceptance. A very serious difficulty was the problem of shrunken kernels and empty nuts. Obviously, with a score related to the weight of the sample before cracking, the inclusion of a number of empty nuts made it impossible to make any accurate correction in the percentages that were used in the score. Penalties did not solve the problem. Also the initial weight of the sample varied with the amount of husk clinging to the shells. From this work it was evident that an acceptable score would have to be formulated on some other basis.

The next approach was to analyze data of this type statistically in an attempt to devise a better scoring system (1). The results from such a study proved valuable in answering such questions as 1) the size of sample necessary to obtain significant differences between samples; 2) the significance of small differences in measurements or in scores and 3) the amount of variation that is normal and without significance in comparing varieties.

The following qualifications were considered essential to a workable schedule:

1) The schedule must be easy to use.

2) The schedule must concern itself with objective qualities or characters which can be weighed or measured. It cannot be concerned with flavor and other characters upon which there may be disagreement and which depend upon personal preference.

3) Characters must be avoided which vary with the treatment of the samples themselves such as color of kernels.

4) It must give a score that will separate samples on small differences.

Considering the problem from these angles and scrutinizing the older schedules, a number of ideas came out. First of all, why include the shells? If shells are discarded a number of problems would be solved, such as the cleaning of the nuts and adjustments for shrivelled and empty nuts. Also, why reduce any of the weights or measures to percentages which only add to the complexity of the score? The actual amount of kernels recovered reflects both the size of nuts and the yield of kernels. Plumpness of the kernels is reflected in the total weight of kernels and does not need to be considered separately.

The important elements in a score were considered to be:

1) The crackability of the nuts of the variety. This is measured by the weight of kernels obtained in the first crack.

2) The yield of the variety. This is measured in the total weight of kernels.

3) The marketability of the product. This can be measured by the number of pieces in the sample. In general, the smaller the number and the larger the size of the pieces the better the marketability.

With this general background in mind, many samples were tested and the results published in the 1945 report[1]. In order to secure the data needed the kernels of the individual nuts in the samples were weighed separately.

NOTE: All samples were cracked with the (John W.) Hershey nut cracker.

Some of the conclusions drawn from these tests were as follows:

1) Using kernel weights only gives a rapid and accurate test of differences between varieties.

2) Ten nuts are adequate for a single sample.

3) The location of the tree with reference to climate and soil is probably the most important single factor influencing kernel yield. No evidence was obtained, however, to indicate that the varieties ranked significantly different at different locations.

4) If reasonable care is used in cracking the differences due to different operators tend to be non-significant.

The statistical proof that a ten-nut sample is adequate and that differences between operators are not significant are two findings that are important in setting up a schedule.

During the past year further testing has been done, in which scores were computed from ten-nut samples.[A] The samples had preliminary cool, dry storage to assure comparable moisture content. Enough nuts were cracked in each sample to secure ten that were well filled. Empty nuts were recorded. The following data were kept for each sample:

1) The weight of the kernels recovered in first crack in grams.

2) The total weight of the kernels in grams.

3) The number of quarters and number of halves recovered.

Scores were computed as 1) the weight of the first crack in grams plus 2) half of the total weight of the kernels recovered in grams plus 3) the number of quarters divided by four and, 4) the number of halves divided by two. In this score, it was considered that the crackability of the sample was measured by the weight of the first crack; the yield, by the total weight of kernels secured from the sample; the marketability by the number of quarters and halves. From the use of this schedule scores were secured ranging from 83.9 for the variety Thomas grown in Maryland to 37.4 for the variety Huen, which is a small nut giving relatively small kernel yield.

Analyses of the data to determine the percentage of the score that was derived from each component showed that crackability as measured by the weight of the kernels recovered in first crack gave an average of 54% of the score with a range of 49 to 58 for the different samples; yield, as measured by total weight of kernels divided by two, 31% with range of 27 to 34%; marketability measured by number of quarters divided by four 14% with range of 10 to 22% and number of halves divided by two 1%. The percentage of the score derived from the number of halves was so small as to be negligible. It seemed better, therefore, to base the score on only three elements, namely, the weight of the first crack, the total yield of kernels and the number of quarters recovered from the sample.

On this basis the problem becomes that of deciding the weights that should be given to these three components. The score as set up emphasizes the crackability of the variety much more than its marketability. This seems logical because the value of a variety is in large part dependent upon the ease of recovery of the kernels on first cracking. Several different combinations of the weighting of these three components were considered and it was decided that the most logical was to weight the elements as follows: 1) The weight of first crack in grams. 2) The total weight of the kernels divided by two and 3) the number of quarters recovered divided by 2. If there are halves, each half would count as two quarters.

Table I. Average scores from 18 black walnut samples cracked by three operators and computed by two scoring systems.

Scoring Systems[3] —————————— Variety Source Year I II points points Thomas Maryland '46 83.9 93.1 Snyder Ithaca, N. Y. (A) '46 81.8 89.2 Ohio Maryland '46 79.5 88.9 Thomas Ithaca, N. Y. (A) '46 76.4 85.5 Norris Tennessee '45 76.1 83.9 Stambaugh Ithaca, N. Y. (A) '46 75.9 81.0 Stambaugh Ithaca, N. Y. (A) '46 74.0 83.2 Thomas Tennessee '45 71.5 79.6 Thomas Ithaca, N. Y. (B) '46 65.7 74.6 Cornell Ithaca, N. Y. (C) '46 59.3 67.6 Stabler Maryland '45 56.9 64.5 Cresco Ithaca, N. Y. (A) '46 55.8 65.2 Seedling No. 1 Geneva, N. Y. '46 52.7 62.2 Seedling No. 3 Geneva, N. Y. '46 50.6 59.0 Brown Ohio '45 49.7 59.4 Stabler Tennessee '45 47.5 51.4 Seedling No. 2 Geneva, N. Y. '46 44.4 52.2 Huen Iowa '46 37.4 44.9 Least significant difference (5%) 6.3 6.6

[Footnote 3: Score I=Weight (grams) 1st crack + Total weight (grams) + —————————— 2

Number quarters + Number halves ———————- ——————- 4 2

Score II=Weight (grams) 1st crack +

Total weight (grams) + —————————— 2

Number quarters ———————- 2 ]

Calculating the percentage of each component in the total score on this basis gives crackability 48%, yield 27%, marketability 25%. This schedule gives relatively more weight to marketability as against the other two components. The average scores of 18 samples cracked by three operators and calculated on both the above described schedules are given in table I.

The table shows that the rank of the different samples was not changed materially by using only the three components, except in a few cases in which there were an appreciable number of halves. The Stabler has many one-lobed nuts which increase the number of halves recovered. It is to be noted that with both schedules the least significant difference at the 5% level is about 6 score points.

Table II gives the score calculated by schedule II for five samples, each cracked by six operators. The difference between operators is not significant but the difference between varieties is highly significant.

Table II. Scores from five samples of black walnuts each cracked by six operators according to scoring schedule II.

Operators ————————————————— Variety Location Year 1 2 3 4 5 6 Average

Snyder Ithaca, N. Y. '46 89.2 87.3 78.9 94.4 87.5 91.5 86.5 Thomas Ithaca, N. Y. (A) '46 83.5 79.2 83.1 78.0 84.2 83.8 83.6 Thomas Ithaca, N. Y. (B) '46 73.1 67.4 73.4 74.1 69.6 83.8 73.6 Cresco Ithaca, N. Y. '46 66.0 69.2 63.1 67.2 68.5 60.2 65.7 Brown Ohio '45 62.5 51.0 65.4 60.4 48.1 64.8 58.7 ————————————————————————————————————- Average 74.9 70.8 72.8 72.8 71.6 78.8 73.6 Least significant difference (5%) for variety averages 6.2

A third scoring system, involving 1) weight of kernels in grams for the first crack, plus 2) total weight of kernels, 3) all divided by the number of marketable pieces (as counted following sifting on a 1/4" round hole screen) was tried, and the resulting ranking of the varieties was very similar to that obtained with systems I and II. The results from this system appeared to be the most precise, but it was not considered as generally acceptable as system II, since the latter would be easier to record and calculate.

It is the opinion of the authors that Schedule II gives a score that estimates very well the relative merit of the samples tested as to crackability, yield and marketability. It is simple to use and the only equipment required is a scale accurate to 1/10 gram. Calculations are reduced to a minimum and the characters used are not dependent on judgment of the individual making the test. It should be pointed out, however, that differences in score of less than six points are not significant on the basis of testing done to date. As more tests are made this value may be reduced. The schedule should serve as a measure to establish differences between varieties, particularly when a considerable number of tests are made. It can also be relied upon to measure differences due to the location of trees of the same variety, variation of the same variety from year to year in the same and in different locations and differences of a similar nature. In ranking varieties which have scores within the limits of variability, it will be necessary to use judgment as to small differences of appearance. No scoring schedule can be expected to entirely eliminate the judgment of experts. Also it must be realized that characters other than the nuts, such as bearing habit, hardiness, yield of trees, disease resistance and the like must be considered in finally establishing the value of a variety.

References Cited

1. Atwood. S. S. and L. H. MacDaniels. Tests of black walnut varieties for differences in kernel yields. N.N.G.A Rept. 36: 44-50, 1945.

2. Berhow, Seward. Black walnut variety tabulations. N.N.G.A Rept. 36: 38-43, 1945.

3. Bixby, W. G. Judging nuts. N.N.G.A. Rept. 10: 122-133, 1919.

4. ——. The 1929 contests and the method of testing used. N.N.G.A. Rept. 22: 42-63, 1931.

5. Drake, N. F. Judging black walnuts. N.N.G.A. Rept. 22: 130-137, 1931.

6. ——. Black walnut varieties. N.N.G.A. Rept. 26: 66-71, 1935.

7. Kline, L. V., and S. B. Chase. Compilation of data on nut weight and kernel percentage of black walnut selections. Am. Soc. Hort. Sci. Proc. 38: 166-174, 1941.

8. Kline, L. V. A method of evaluating the nuts of black walnut varieties. Am. Soc. Hort. Sci. Proc. 41: 136-144, 1942.

9. Lounsberry, C. C. Measurements of walnuts of United States. N.N.G.A. Rept. 31: 162-127, 1940

10. MacDaniels, L. H. Report of committee on varieties and judging standards. N.N.G.A. Rept. 28: 20-23, 1937.

11. ——. Is it possible to devise a satisfactory judging schedule for black walnuts? N.N.G.A. Rept. 30: 24-27, 1939.

12. ——, and J. E. Wilde. Further tests with black walnut varieties. N.N.G.A. Rept. 34: 64-82, 1943.



Test Plantings of Thomas Black Walnut in the Tennessee Valley

SPENCER B. CHASE, Tennessee Valley Authority

Native black walnut occurs abundantly throughout most of the Tennessee Valley. Practically every farmer has at least one "favorite tree" and each fall he collects nuts from that tree and stores them for cracking during the winter. In some sections of the Valley walnut cracking in the home is of considerable importance. Each year, some million and a quarter pounds of kernels are cracked out at the five modern cracking plants located in or adjacent to the Valley. Utilization of the crop is becoming more and more complete.

In early studies of native nut trees, TVA recognized the possibilities of black walnut, especially the improved varieties. Here was a tree that produced not only valuable nut crops but also cabinet wood without equal; in addition, it was a desirable pasture shade tree. Black walnut has long been a favorite among farmers, but few of them had ever heard of improved black walnuts. Along with TVA, the state agricultural extension services saw the advantages of the improved varieties and were eager to test them under Valley conditions. And so it was that a cooperative testing project was developed. TVA produced the trees and the seven Valley state extension services distributed them to farmers for test planting.

The Test

The Thomas walnut was used in these test plantings for several reasons. In the first place, it produces large, rather thin-shelled nuts with good cracking qualities. Few varieties are more easily cracked with a hammer or a hand-operated cracking machine. In addition, fast growth is characteristic of the variety and it should produce merchantable sawlogs earlier than the common walnut. Despite its northern origin, 5-year-old plantings at Norris, Tennessee, seemed well adapted to Valley conditions. No other variety at the time offered as many advantages.

Test planting was begun in Tennessee in 1939 and then it was extended to the other Valley states as more trees were propagated. For the most part, planting sites were selected by extension foresters and county agents. If the tests were successful they would automatically become demonstrations, so special attention was given those areas where walnut cracking in the home was an important enterprise. Many of the test plantings were located in communities that had been organized for the study and application of improved farming methods. In general, farmers planted the trees in low, fertile spots not suitable for other uses, along fences, or in pastures if they could be protected from livestock.

Through 1946, 9,614 trees were planted in 3,286 test plantings. They were scattered all over the Valley, in 92 of its 125 counties. The number of trees per planting varied with the availability of good walnut sites. Generally, there were 2 to 4 trees in each planting.

The Results

Getting survival and performance data on these widely scattered experimental plantings presented quite a problem. Examination of a few plantings showed that trees given reasonable care had survived and were beginning to bear nuts. So in 1946, the farmers who had planted the trees were polled by mail for an overall evaluation of the plantings. Questionnaires asking for information on survival, growth, and bearing were sent by the state extension foresters to 3,274 farmers. The return of questionnaires was excellent. Forty-two percent came back and three-fourths of them were filled out completely.

Survival and Mortality Causes. Eighty-one percent of the 1,373 plantings reported on were still active in 1946; that is, they still had at least one living tree. Survival reports received on 3,831 trees planted showed that 2,439 or 64 percent of the trees were living in 1946. Survival was best in the portion of the Valley north and east of Chattanooga; 84 percent in Virginia, 71 percent in North Carolina, and 66 percent in eastern Tennessee. South and west of Chattanooga survival percent was lower: 62 in Georgia, 61 in western Tennessee, 54 in Kentucky, 45 in Alabama, and 26 in Mississippi (Table 1).

Causes of mortality, as reported, were classified in five categories; losses prior to establishment, livestock and destruction, drought, insects and disease, and unknown (Table 1). Cause of mortality was listed as unknown for 42 percent of all trees reported dead. Field experience leads us to believe that most of the trees in this category probably succumbed to improper planting or complete neglect following planting. Many persons do not follow planting instructions; they often substitute their own methods with disastrous results.

Among the reported known causes, drought killed most of the trees—29 percent. We know black walnut is very susceptible to dry weather after transplanting. Weather records for the area show that the early growing season of 1941 was exceptionally dry; 1942 was also drier that average; in 1943 and 1944 near drought and drought conditions prevailed throughout most of the Tennessee Valley. Weather is usually blamed when a tree dies without apparent cause, but in this case the reported mortality due to drought appears reasonable.

Livestock, mowing, fire, and intentional removal were reported to have caused 13 percent of total mortality. Cows are curious animals and newly set trees seem to arouse all the curiosity in their make-up. Horses and cows apparently do not relish the foliage of walnut trees but they do bite at it, and in so doing usually break down the branches to such an extent that the tree dies. Some trees were accidentally destroyed simply because they had been forgotten. The next highest mortality cause reported was pre-establishment loss; this was blamed for 9 percent of the deaths. Losses resulting from delayed planting were placed in this category, also those where the report was "trees failed to leaf out." Insects and diseases were reported as causing 7 percent of the mortality.

Growth and Bearing. Those who plant improved black walnut trees naturally want to know how soon they will begin bearing. This survey shows that bearing begins much earlier than most people thought. Trees in 32 percent of the plantings established between 1939 and 1944 were bearing by 1946. Of these 342, 113 began bearing 2 to 4 years after planting; 120 bore their first crop after 5 years; 109 began bearing after 6 to 8 years (Table 2). According to the reports, the earlier plantings were slower to come into bearing than the later plantings. This probably is not a true picture. We suspect that after six or eight years the actual date of first bearing had been forgotten in many cases.

Growth was reported in terms of total height for each tree. These heights were then converted to annual growth rates for trees 3 to 8 years old and placed in arbitrary classes are follows: low (less than 1 foot) medium (1 to 2 feet), and high (over 2 feet). Test plantings in North Carolina had the highest growth rate; those in Mississippi, the lowest. In other states, growth rates fell between these two and were quite similar for the most part (Table 3). Average for all trees was 1.6 feet per year. Trees averaging less than one foot of height growth per year were slow to come into bearing. Only 14 percent of the trees in the low growth rate class were bearing. On the other hand, 71 percent of the trees with a high growth rate had come into bearing. Growth of black walnut, following recovery from transplanting shock, depends on site conditions and tree care. Trees set in fertile soil with an adequate moisture supply and kept free of livestock and other damage make rapid growth. Trees set in poor, thin or droughty soil do not make much growth if they survive at all. Black walnut is very sensitive to any wounds and, if subject to mechanical or livestock damage, growth is retarded.

Cases of exceptional growth and bearing were reported. One in eastern Tennessee is worthy of brief description. There were two trees in this planting set approximately 40 feet apart. One was on the edge of a garden; the other, in a chicken run. In seven years the first tree grew to a height of 32 feet—an average growth of 4.5 feet a year. It began bearing in 1943 and produced a crop of nuts each year up to the time of the survey. The 1946 crop, reported as a light one, yielded 3.5 pounds of kernels. The other tree, shown in Figure 1, was 18 feet tall, having averaged 2.5 feet a year. It also began bearing annual crops in 1943, and in 1946 it had a very heavy crop for its size, yielding 2.5 pounds of kernels. Here are two Thomas trees of the same age planted practically side by side; one is almost twice the size of the other, but they both began bearing annual crops three years after planting.

Field Survey in Sample Area. To check on the adequacy of the questionnaire survey, 108 test plantings in eastern Tennessee were visited and inspected. Forty of these had been reported on by mail; 68 had not. In general, the trees had been planted on the best sites available. Some were set out in farm orchards (Figure 2); a large number were planted in yards as combination nut and shade trees (Figure 3).

Field examination of the 40 plantings which had returned questionnaires revealed conditions very similar to those reported (Table 4). Survival was found to be 75 percent compared with a reported 77 percent. Average tree height was reported as 9 feet; actual height averaged 11 feet. There was some hesitancy in reporting tree deaths caused by livestock; 4 percent was reported while 23 percent was found. Such mortality was usually listed as unknown on questionnaires.

Information collected by field examination of 68 plantings which had not returned questionnaires and the 40 plantings which had returned questionnaires is shown in Table 4. Trees were found to be 2 feet taller in the 68 plantings but these trees averaged one year older than trees in the 40 plantings. Trees in the 68 plantings averaged 13 feet in height compared with 11 feet. Average age at first bearing was very similar. And here is a revealing discovery; livestock, mowing, and fire were responsible for 47 percent of the tree mortality in the 68-planting group, compared with 23 percent in the 40 plantings. This is perhaps one reason why the persons involved in these 68 plantings did not return questionnaires; it also explains most of the poorer survival. A large number of trees were planted in pastures and elsewhere without adequate protection from livestock. Even when cattle guards were used they were generally too small or weak for tree protection. Severe livestock damage resulting in poor growth and eventual death of trees was encountered frequently. We are inclined to believe that livestock accounted for a much higher percent of tree mortality than that reported in this survey.

The high percent return of questionnaires in this survey, followed by a field check in a sample area, provides a good picture of Valley-wide plantings. Since survival was found to be lower in plantings which did not return questionnaires, an actual overall survival of 64 percent may be slightly high. Other spot checks in the field will give more information on this point.

Discussion

Interest in improved black walnut is mounting in the Valley. As the test plantings came into bearing farmers were quick to see the superiority of these nuts over the wild ones to which they had been accustomed. Word spread from farm to farm, and as a result there has been an increasingly large number of inquiries about sources of improved varieties and cultural treatments. The interest was reflected in the questionnaire survey. Nineteen percent of the questionnaires returned contained unsolicited comments of one kind or another. A large percentage of them showed evidence of interest such as: "the nuts are large and easy to crack," "where can I get more grafted trees?" Only 7 percent implied disinterest: "the trees are slow growing," "the nuts are faulty."

This test-planting project will be completed in 1948. The plantings have already yielded much valuable information on the Thomas variety; they will yield much more as the trees become older. Further studies are planned on nut yield, nut quality, and tree growth in relation to the varying conditions existing in the Tennessee Valley.

Summary

Farmers in the seven Tennessee Valley states established 3,286 test plantings of Thomas black walnut in cooperation with state extension services and TVA during the period 1939-1946. A questionnaire survey in 1946 showed 81 per cent of the plantings still active and 64 percent of the trees living. Tree growth averaged 1.6 feet per year. Age at first bearing varied from 2 to 8 years, with 5 years most frequently reported.



Table 1.—Number of Questionnaires Sent and Returned, Reported Tree Survival and Cause of Tree Mortality by State.

Questionnaires Trees Reported State Sent Returned Planted Living no. pct. no. pct. Alabama 161 44 274 45 Georgia 50 28 26 62 Kentucky 174 49 241 54 Mississippi 19 58 72 26 North Carolina 586 40 733 71 Tennessee, East 1,386 40 1,516 66 Tennessee, West 720 44 809 61 Virginia 180 48 160 84 All 3,276 42 3,831 64



Reported cause of tree mortality

Pre-estab Livestock, Insects, Total Planted -lishment destruction Drought diseases Unknown Trees Lost pct. pct. pct. pct. pct. no.

Ala. 11 7 51 2 29 150 Ga. 30 10 0 20 40 10 Ky. 2 2 46 4 46 112 Miss. 19 4 49 0 28 53 N. C. 15 16 12 13 44 223 Tenn. (E.) 7 18 20 7 48 515 Tenn. (W.) 8 9 38 7 38 318 Va. 32 12 12 4 40 25 All 9 13 29 7 42 1,406

Table 2. Number of Bearing Thomas Plantings Established 1939-44, by Age of First Bearing and Growth Class.

Plantings Age in years at first bearing Growth rate Year Number 2 3 4 5 6 7 8 Low Medium High

1939 27 1 6 10 6 4 1 19 7 1940 112 2 14 39 41 16 9 58 45 1941 89 1 4 17 35 32 1 58 30 1942 71 1 12 18 40 1 34 36 1943 38 1 13 24 1 21 16 1944 5 5 2 3 All 342 3 36 74 120 83 22 4 13 192 137

Table 3. Tree Survival, Growth, and Percent Bearing by State and Year of Planting

Plantings Trees, Growth, Bearing State reported survival annual trees number number feet percent

Alabama 71 124 1.6 65 Georgia 14 16 1.5 18 Kentucky 85 129 1.5 71 Mississippi 11 19 1.0 29 North Carolina 235 518 1.9 25 Tennessee, East 553 1,007 1.5 32 Tennessee, West 318 491 1.6 32 Virginia 86 135 1.6 0

Year of planting

1939, 1940 255 627 1.6 64 1941, 1942 499 693 1.6 44 1943, 1944 326 558 1.6 18 1945, 1946 293 561 1.5 0 All 1,373 2,439 1.6 32

Table 4. Data Obtained from Returned Questionnaires and Actual Field Examination of 40 Plantings and Field Data Only on 68 Plantings.

Data on 40 Plantings Data on 68 Plantings Questionnaire Field Field Tree Survival, percent 77 75 51 Average Height, feet 9 11 13 Cause of Tree Mortality, percent Pre-establishment 33 42 11 Livestock and Other Destruction 4 23 47 Drought 13 0 0 Insects and Diseases 8 4 2 Unknown 42 31 40



West Tennessee Variety, Breeding and Propagation Tests, 1947

AUBREY RICHARDS, M.D., Whiteville, Tennessee

I surely wish I could have made the trip to the Northern Nut Growers Association meeting, but I simply had "too many hens setting" at that time. I've been waiting for you [the Secretary] to show up down here for the big news—at least it is to me—if it holds up. If you have ever tried to propagate heartnuts on Japanese walnut you know what it means.

Here it is: Rhodes, Wright and Fodermaier heartnuts patch-budded on 10 Japanese understocks (all I had) took 100%. The same 3 varieties as a control on black walnut gave a take of only 80%.

These trees give me a chance to check on the performance of black versus Japanese stocks for these varieties. From last year's propagation, Rhodes on black is beating Rhodes on Japanese and Bates (which was not used this year) seems fully as good on black walnut stocks.

An isolated tree of Bates did not set a nut. Its pollen all shed before the pistils were receptive. An isolated tree of Rhodes bore a full crop.

Incidentally, a weak chlorine bleach (Clorox) after these heartnuts are hulled does for them what peroxide does for the ladies and makes them look very inviting.

Stambaugh again led in topworked black walnuts, bearing its second consecutive full crop on a 3-year graft. It seems to be immune to whatever it is that causes the other nuts to turn black, shrivel and drop off from the time they set until near maturity. Thomas was second. Snyder, Sparrow and Myers had no crop. I budded 25 more trees of Stambaugh this year.

The Carpathian Persian walnut that we pollinated this spring with Wright heartnuts [no other walnuts were shedding at the time] matured a nice, large, rather pointed, heavy nut. It also matured another nut higher on the tree than we could reach with the catkins, but I'm sure it's a blank. It is still more pointed than the well-filled nut. The good nut is stored for planting.

Rush hazel that set fruit last year with the help of a bouquet of native [West Tennessee] catkins set only 5 nuts this year "on its own." These I have also stored to plant.

I didn't have enough stocks to utilize all the pollen-sterile Japanese chestnut buds you sent me [in early September]. I put in most of them, even in some cases several to the stock to see what percentage of takes we would get with the twin T. [See 1946 Report of N. N. G. A., pp. 87-88, for a description of the Twin T budding method.—Ed.]

Here are the percentage takes for chestnut propagation this year. Of course I don't know how many of these buds will later drop off.

1. Pollen-sterile Japanese on Japanese stock. Late summer buds 100%

2. Austin Japanese on Japanese Stock. Late summer buds 86%

3. Hobson Chinese on Chinese. Late summer buds 75%

4. Zimmerman Chinese on Chinese. Late summer buds 50%

5. Colossal hybrid on Japanese stock. Spring grafts 60%

I had a nice crop of Chinese chestnuts on my young Hobson and Zimmerman trees. The 1947 nuts were exceptionally large. One 3-year seedling bore 1 bur with 3 nuts fully as large. Connecticut Yankee bore for the first time, 3 nuts to a bur, but very small, scarcely 1/2" in diameter. (You will notice I budded none of this variety!) (Perhaps mislabeled seedling.—Ed.)

I have about 100 nuts from isolated trees that were hand pollinated, as follows: Austin x Hobson, Austin x Zimmerman, Hobson x Austin and Hobson x Zimmerman.

I have altogether 3 quarts of select nuts stored in the refrigerator. So far they are keeping nicely. (I dusted them with Fermate, hope it doesn't affect germination.)



Notes on Some Kansas and Kentucky Pecans in Central Texas

A letter to the Secretary from O. S. Gray, nurseryman at Arlington, Texas, October 28, 1947, has some interesting notes on two standard northern pecans, three new varieties from Kansas, and the Moore variety, one of the earliest maturing among southern pecans:

We are propagating Major and Greenriver from Kentucky; Coy, Tissue Paper and Johnson from southeastern Kansas; and Brake from eastern North Carolina.

Several years ago we used quite a few pecan trees of the Moore variety in planting around Tulsa. We though it would be a dandy because of its early maturity in the fall. I find that early fall maturity is only one important factor. The other is the date of starting growth in the spring. Moore seems to start out a little early in the spring and that disadvantage seems to limit it in the Tulsa, Oklahoma area. I also believe this might be a factor in using this variety in northern locations. [Moore originated in north Florida from Texas seed—Ed.]

I have been considerably impressed with the Johnson variety. It matures two or three weeks ahead of Moore in the fall. The only data that I have was made in 1944 when Moore buds began to put out on March 25, Stuart and Success—April 5, Johnson—April 5, Coy and Major—April 8, Greenriver and Tissue Paper—April 10.

The Johnson matures on our place several weeks ahead of Major and Greenriver although I don't have the exact date on maturity.



Experiences of a Nut Tree Nurseryman

J. F. WILKINSON, Rockport, Indiana

In pioneering a nursery as we did in the early days of propagation of Northern nut trees, especially the pecan, it was necessary to first locate parent trees in this section that were worthy of propagation, in order that the nursery stock produced from them would be hardy in this and more northern territory.

Along the Ohio and Wabash rivers and their tributaries many thousands of large seedling pecan trees grew naturally, and to locate some of the most worthy ones for propagation took the combined efforts of all of us in this section who were interested, as well as the aid of the tree owners and nut gatherers.

In the year 1910 three nut nurseries were established here in Southern Indiana, two of which have long since been discontinued. Before that time a very few propagated pecan trees had been produced in an experimental way by some fruit tree nurserymen.

Little did I realize at that time the trials and headaches that lay in the path I was to travel in this venture, such as locating the parent trees, securing the graft and budwood from them, learning to keep this wood from time of cutting until used, methods of propagation, trying to educate the prospective tree buyer as to the value of these trees, and to believe that pecan trees could be transplanted, and that they would bear if the taproot had been cut, and many other things.

Production of nut trees in nurseries in this northern territory is so different, and more difficult than in the Gulf Coast country, where I spent a part of two seasons hoping to get information that would be of value here. What I learned there was of little or no value here, so it was up to us to solve our own problems in this section by experience, as there was very little in print at that time on Northern nut tree propagation.

One of our first problems was to learn to keep cions from time of cutting until time of use, not knowing when that time was. We tried all times from March until May, having little success at any time. At first we kept the scions in a cold storage plant in Evansville, and at a temperature of around 32 degrees, and in wet moss. Later we found it much better to keep scions at home in a cellar at a higher temperature, and in only slightly dampened sphagnum moss.

In the beginning our efforts were mostly in grafting, then after a year or two of failure, probably largely due to the way we kept our scions, we had some results at the McCoy Nursery, with scions kept at home. The McCoy Nursery was about four miles from my place, and located in a sandy soil with a near quicksand sub-soil. At that location they were later reasonably successful in grafting, using the modified cleft graft.

My nursery is in clay soil with a hard stratum of soil three or four feet below the surface, and because of this I have been unable to graft pecans in the nursery, though I have tried every known method, and under all conditions. I could successfully graft at the McCoy Nursery, then use the same scion wood and the same method at home, but have a complete failure; therefore, I turned to budding entirely on pecans in the nursery.

It is somewhat different with walnut—I can get fair results with walnut grafting at times, though I do very little of this, as more than 95% of my walnut trees are produced by budding.

I do a lot of topworking on native seedling nut trees for others. Mr. Sly, who is with me, and I make one or more of these trips each spring. For this work I use only the slip-bark method, shaping the scion a little differently from any other I have ever seen used. This has given splendid results everywhere I have used it, which has been over the territory from Ohio to Oklahoma.

A certain amount of allowance is made in this work as to safe drainage of the stock, depending on weather and soil conditions, which vary as, to season and location.

I do practically all of my nursery propagating by budding, and one of the most essential things is to have favorable sap conditions in budwood as well as in stocks.

On walnut I use only the current season's growth of wood for budwood, and it must be reasonably well matured. Very often sap in the stock may show signs of leaving before budwood is matured enough for use, and only the riper buds near the base of the bud stick can be used, in which case the rest of the buds on the bud stick are lost. Sometimes sap in the stocks can be held a few days longer by cutting a ring around the stock above the place where the bud is to be placed, which checks the flow of sap to the upper part of the stock. Sap in the stock must be in a favorable condition to hope for good results.

In budding pecan it is different. Either the current or the past season's growth may be used with about equal results, though the current season's buds must be well matured. Very often in a dry season when there is evidence of sap leaving the pecan stocks earlier than usual and the current season's buds are not well matured, I use the past season's growth until the new growth is mature.

A nut tree nurseryman has experiences that are both pleasant and unpleasant in selling trees as well as producing them. This is probably well known to all of you who have produced and sold nut trees. It is astonishing how many questions (some of which are amusing) the public can ask, and very often those that ask the most questions, leading one to believe they are a good prospect for a large order, may order only one or two trees, or none at all. Then there are those who have never bought a nut tree before, and when they see their first one are dissatisfied because it does not have a root system like a fruit tree; and there are a few who will try to get replacements whether they are entitled to them or not, and usually they are not; for, regardless of the instructions given for the planting and after-care, they will neglect them, then complain if they have a loss, and certain experiences have led me to believe they claim loss before having it.

Many seem to think that a nurseryman should guarantee his trees to live when planted by the purchaser. To do this would be assuming the responsibility of the handling, planting and after-care of the planter, which would make it necessary for the nurseryman to put a price on his trees that would take care of a lot of replacements to the more careless ones who would have losses, and be very unfair to those who take good care of their trees, and have little or no loss, as they would be standing part of the loss of the careless ones.

The most a nurseryman can do is to produce the best trees possible, dig them carefully, pack them in first class condition and ship them immediately.

Discussion after Mr. Wilkinson's paper.

Dr. Crane: "Minor elements are important in plant nutrition The problem of deficiencies is going to become very important. We do not keep the livestock we did and we are not returning to the land the manure and other fertilizers that contain the elements the trees need. Nitrogen, phosphorus, and potash, also magnesium are needed. We are taking more from the soil than we are putting back."

Corsan: "In Cuba there are hundreds of sharks. These make fine manure, wonderful for nut trees."

Prof. Slate: "How many sharks would you need for an acre of land?"



Morphology and Structure of the Walnut

C. C. LOUNSBERRY, Iowa State College

This subject, the structure of the walnut, is discussed in its relation to propagation. Catkin bearing nut trees, such as the walnut, have a refined structure that makes grafting difficult. Structure, rather than form of walnuts, suggests treatment under the headings, bark, cambium, wood, roots, pith and buds, as well as the sap that permeates them.

Bark: When the bark of the walnut is cut, as in budding, it is difficult to tie down so it will not curl and yet not strangle the bud. The wax-like covering of the bark is thin. However, the bark itself will stay green two months or more if weather is cool.

Cambium: The cambium dries quickly when exposed to air, and must be kept covered. Grafted walnuts show callus growth from the cambium, and also from the pith of stems and the endodermis of the root.

Wood: The wood of the walnut is diffuse porous, brittle, straight grained, and easily split. The wood must be cut diagonally to get sufficient tension to hold the scion in grafting. The branch grows rapidly in a short season, May 15th to July 1st in central Iowa. The upper two-thirds of the one year growth is usually light weight with pith of large diameter. The base of the one-year growth is the best for scions. Some varieties of walnut as for example the Thomas, have relatively large one-year growth and more scions can be cut from its branches than from the wood of Ohio which is small and willow-like.

Measurements taken in 1940 on 118 common black walnut seedlings planted in 1939 showed 9/16" average diameter of seedling at crown, 5/16" average diameter of pith at crown; 3/8" average diameter of seedling at top; and 1/4" average diameter of pith at top; 3.26 inches average length of solid pith above crown; 2.91 inches average length of solid pith in root below crown.