Propagation by Grafting
A search of the literature failed to reveal a discussion of any method of bench grafting with hickories, although presumably it must have been tried. Propagators may have been discouraged in using bench graft methods by the sparse roots usually found on two-year seedlings. It is suggested that undercutting and root pruning the seedlings several times while in the nursery row should produce a more adequate root system which would transplant well after grafting. Brison(5) remarked that bench grafting is not used in the propagation of pecans in Texas on account of transplanting difficulties.
Commercial nurserymen now prefer to bud hickories and pecans rather than to graft, but formerly Reed(15) reported the whip-and-tongue method was used on thrifty one-year seedlings in the nursery row. It is conceivable that the cleft graft could be used at this stage when the diameter of stock and scion are quite similar but no record of its use is available.
Top-working or grafting in the branches is commonly practiced on seedling trees and sometimes used to change varieties in the orchard. Reed(15), Sitton(19), Rosborough et al(18), MacDaniels(11), and Stoke(22) have described various methods that have proven successful. Practically all agree that the bark graft or a modification thereof is best. Morris(12), Benton(3), MacDaniels(11), Wilkinson(25), and others have shown that a greater per cent of survival is secured when the stocks are cut 10 days to 2 weeks before grafting. During this time the stubs heal somewhat and excess bleeding is decreased. It has been reported by Becker(2) that the success of walnut grafting is greater when the grafts are set just after the leaves are full grown but no such data is available for hickories. The use of paper bags or other shading device over the scion is advocated by Morris(13), MacDaniels(11), Shelton(20) and others.
Propagation by Budding
Patch budding is now almost universally used by commercial nurserymen in the propagation of hickories and pecans. Patches are usually cut with a double-bladed knife although some use the rectangular Jones patch-budding tool. The "plate" or "skin" bud is also used to some extent. The thick bark of hickories and pecans discourages the use of the shield or "T" bud.
Budding is usually done in late summer with mature buds of the season growth which remain dormant until the following spring. Occasionally dormant budwood taken in winter is held in cold storage until the bark of the stock slips in the spring. These spring-set buds are forced the same season by cutting the stocks back shortly after setting. Patch-budding is described by Reed(15) and by Rosborough et al(18). Reed(15) mentioned that it may be advisable to make the cuts in the stock from one to three weeks before the bark is removed so that the healing process may be under way at the time the bud patch is inserted.
Storage and Handling of Scions and Budwood.
Shelton(20) reported an easy and unique method of keeping scions moist by storing in a closed container with a small amount of sodium sulphate (Glauber's salt). Slightly moist peat moss is an excellent packing material. Brison(4) reported that a temperature of 32 deg. F to 38 deg. F in storage is satisfactory for keeping the buds dormant, and that a few days from 80 deg. F to 85 deg. F will stimulate cambial activity so that the patches will "slip" easily when cut. Scionwood is sometimes dipped in wax, paraffin, or plastic resin before storing in order to prevent loss of moisture and guard against pathogenic organisms.
Waxes and Wound Dressings
Sitton(19) used a large number of variously formulated waxes on pecan and found that the most successful from the standpoint of graft survival was one composed of 10 parts rosin, 2 parts beeswax, and 1 part filler such as kieselguhr, talc, or aluminum powder. Under Louisiana conditions a light-colored wax was preferable to dark colored one. Asphalt emulsions were not satisfactory.
Rootstocks and Interstocks for Hickories
Reed(16) summarized the rootstock studies at Beltsville, Maryland, by stating that pecans were best on pecan seedlings and that shagbarks were successful on either shagbark or pecan rootstocks. He reported a lack of congeniality between shagbark and bitternut hickory. Smith(21), however, found that pecan stocks were unsuccessful for shagbarks as few scions lived and growth of those which survived was poor. He also reported that bitternut was practically as good as shagbark for shagbark varieties. He stated that pignut was absolutely useless as a stock for shagbark. Weschcke(24) reported that shagbark varieties grew well on bitternut but also indicated that a slow growing variety would be stimulated in growth by working on pecan stocks which are more vigorous in growth than the other hickories. Dunstan(8) reported that pecan provides a perfectly satisfactory rootstock for shagbark, shagbark hybrid, and hican varieties. A number of varieties have been tested over a period of several years with favorable results as shown by lasting unions and better than average yields.
The Fairbanks hybrid has often been used as an intermediate stock between bitternut and some shagbark varieties and Last(10) has stated that the variety Rockville is useful for interstock purposes on account of its exceptional vigor.
Hickories and pecans have long tap-roots with few branches and hence do not transplant well. Some few have grown the seedlings for one year in beds underlain with wire screen netting or have undercut the seedlings to promote branching of the roots. The stocks must grow two years from seed to attain a diameter permitting of patch budding and must remain one or two years more to allow the scion to form a tree. The resulting plant is large in both root and stem and requires careful handling in digging, shipping, and planting in the permanent location. The vicissitudes which befall the production of the northern hickories are often so great as to discourage nurserymen who otherwise would grow them. This is an unfortunate fact but a real one, as the would-be purchaser often learns when he attempts to buy named varieties of hickories. The situation with the pecan is much better, due perhaps to the greater demand for such trees but also to the greater ease of propagation in general nursery practice.
Good varieties of hickories bear good nuts and more people should plant good trees which should be produced by nurseries with well-branched fibrous root systems so that they will transplant easily. Research is needed to determine practical methods of propagation which will permit of inexpensive quantity production of superior named varieties of shagbark and shagbark hybrid hickories.
1. Barton, Lela V. Seedling production in Carya ovata, Juglans cinerea, and Juglans nigra. Cont. Boyce Thompson Institute 8:1-5. 1936.
2. Becker, Gilbert. Notes from Southwestern Michigan. Rpt. North. Nut Grow. Assoc. 28:135-136. 1937.
3. Benton, Wm. A. Report on propagation of nut trees. Rpt. North. Nut Grow. Assoc. 29:90-92. 1938.
4. Brison, Fred R. The storage and seasoning of pecan budwood. Texas Agric. Expt. Sta. Bul. 478. 1933.
5. ——. Personal correspondence. 1952.
6. Burkett, J. H. The pecan in Texas. Texas Dept. of Agric. Bul. 111. 1932.
7. Corsa, W. P. Nut culture in the United States. U. S. Dept. Agric. Div. of Pomology. 1896.
8. Dunstan, R. T. Personal correspondence. 1952.
9. Gossard, A. C. Rooting pecan stem tissue by layering. Proc. Amer. Soc. Hort. Sci. 38:213-214. 1941.
10. Last, Herman. Personal correspondence. 1952.
11. MacDaniels, L. H. Some experiences in nut tree grafting at Ithaca, N. Y. Rpt. North. Nut Grow. Assoc. 28:52-55. 1937.
12. Morris, R. T. Top working hickories. Rpt. North. Nut Grow. Assoc. 11:105. 1920.
13. —— Nut growing. 1931. Macmillan, New York.
14. O'Rourke, F. L. Unpublished data. 1945.
15. Reed, C. A. Nut-tree propagation. U. S. Dept. Agric. For. Bul. 1501. 1926.
16. ——. Hickory species and stock studies at the Plant Industry Station, Beltsville, Md. Rpt. North. Nut Grow. Assoc. 35:88-121. 1944.
17. Romberg, L. D. Use of nurse seedlings in propagating the pecan from stem cuttings. Proc. Amer. Soc. Hort. Sci. 40:298-300. 1942.
18. Rosborough, J. F., F. R. Brison, C. L. Smith, and L. D. Romberg. Propagation of pecans by budding and grafting. Texas Ext. Ser. Bul. B-166. 1949.
19. Sitton, B. G. Pecan grafting methods and waxes. U. S. Dept. Agric. Circ. 545. 1940.
20. Shelton, E. M. Glauber's salt for humidity control in scion storage. Rpt. North. Nut Grow. Assoc. 28:70. 1937.
21. Smith, Gilbert L. Our experience with root stocks. Rpt. North. Nut Grow. Assoc. 40:62-64. 1949.
22. Stoke, H. F. Grafting methods adapted to nut trees. Rpt. North. Nut Grow. Assoc. 37:99-102. 1946.
23. Stoutemyer, V. T. and F. L. O'Rourke. Unpublished data. 1938-1940.
24. Weschcke, Carl. The importance of stock and scion relationship in hickory and walnut. Rpt. North. Nut Grow. Assoc. 39:190-195. 1948.
25. Wilkinson, J. Ford. Preparation of stocks for propagation. Rpt. North. Nut Grow. Assoc. 28:65-66. 1937.
A Root Disease of Persian Walnut
G. FLIPPO GRAVATT, U. S. Plant Industry Station, Beltsville, Md.
On three recent trips to southern Europe I noted large numbers of dying Persian (English) walnuts, Juglans regia, in France and Switzerland and scattered trees in other countries. Dying of Persian walnuts from a root disease of undetermined cause has been reported from various European countries for many years. The extensive dying of mature Persian walnut in a number of areas in southern France is very serious. Farmers and orchardists are discouraged from planting the Persian walnut even though it is a very profitable tree when not attacked by the root disease. In area after area I noted that the farmers had scattered their Persian walnut trees, separating them as much as possible or planting them along the boundary of fields instead of in orchard plantings. They had found too frequently that solid plantings of walnut die from the root disease. The total number of Persian walnuts in southern France has decreased alarmingly in the last sixty years. In Tessin Province in Switzerland many unhealthy Persian walnuts were noted this past summer showing the same symptoms as in southern France.
Studies By French and Italian pathologists have indicated that the fungus Phytophthora cinnamomi is the most likely cause of this dying of walnuts. I was informed that it is worse on soils inclined to be wet or poorly drained at certain times of the year, conditions favorable for attack of many hosts of this Phytophthora. The work reported by B. S. Crandall and me in Phytopathology, March 1945, showed there was a rather direct relation between soil conditions and Phytophthora cinnamomi damage to black and Persian walnut seedlings. Long periods of heavy rainfall were very favorable for an epidemic outbreak of this fungus on walnut and other nursery stock. Another species of Phytophthora, P. cactorum, has also attacked black walnuts in nurseries in eastern United States; this fungus has also been reported on Persian walnuts.
We are interested in receiving reports of the dying of Persian or black walnuts in orchards or rows of trees in the Eastern half of the United States. Persian walnuts suffer from winter injury in many areas and sometimes this injury is confused with the root disease. However, where there are indications of continuing dying of walnuts year after year with a progression from one part to another of the planting, we would like to receive a report.
Some root diseases are difficult to diagnose, especially when the small roots are the parts affected.
The symptoms of the root disease of the Persian walnut in Europe are in many ways very similar to those of the Phytophthora root disease of chestnut and chinkapin in this country as described in the report by Gravatt and Crandall in the Northern Nut Growers Association Proceedings for 1944. In some cases Persian walnuts die slowly and in others death is rapid, with the entire tree browning in summer. Some trees will show less green color than normal during the summer and gradually die over a year or two. Trees in different stages of dying can be seen in the same planting.
Persian walnuts in the Western States in recent years have been dying from a disease of undetermined cause. Dr. Paul W. Miller and others have reported on the black line graft union failure, Armillaria mellea and dying of roots from undetermined causes. As Phytophthora cinnamomi, an imported fungus, is a comparative recent invader of many parts of the west, Dr. Miller is giving the fungus some attention as a possible parasite. On some hosts, this fungus attacks primarily the very smallest roots at certain favorable times of the year, which makes determination of its role as a parasite rather difficult.
Factors That Influence Nut Production
W. B. WARD, Extension Horticulturist, Purdue University, Lafayette, Ind.
The profitable production of fruit on nut trees under cultivation has no doubt been influenced by several factors. Assuming that the present-day seedlings and propagated varieties are winter hardy and the tree of bearing age, 10 to 15 years old, one may expect a reasonable harvest. It is somewhat disappointing to the owner of a single nut tree or for the grower on a semi or commercial basis to find that the tree or several trees have failed to set fruit.
The commercial fruit grower of apples learned, many years ago, that certain varieties when planted in solid blocks failed to set satisfactory crops. Rather than lose several years of growth and expense, the better growers top-worked the trees with a good pollinizer. The result was a profitable harvest of red and yellow apples, or varieties of different maturity. The peach grower liked the looks of a very fine peach and after a short trial found that the variety was not hardy enough to withstand the winter and early spring temperatures. The experiences of the commercial fruit growers could be well used by the nut grower. Only trees adapted to local conditions should be planted regardless of the recommendations of the nurseryman. Hardiness of wood and bud, ample production of pollen, reasonable climate during the growing season, and the control of insects or diseases determine, for the most part, the success of the harvest.
Soils and Fertility
The nut trees require good drainage and a good supply of moisture. A reasonably fertile soil should be selected for a planting site but through mulches, manures, and commercial mineral fertilizers any soil may be built up to a high state of fertility. A weak tree has little chance and may come into bearing too late to be of value for the present owner. The annual growth should be checked each year and, unless 10 to 12 inches of growth has been made the previous year, some means of stimulating more growth should be employed. The hickory, pecan and black walnut, as a rule, make little new annual growth while the Persian or Carpathian walnut, heartnut and chestnut ordinarily produce good annual growth and an abundance of good foliage grown where it counts the most, on the new wood.
Those who have observed the growth habits of nut trees know that the catkins are found on last year's growth, or two year old wood, and the fruiting flowers at the end of the present season's growth. There are times when the new growth developed in a matter of a few days to sometimes as long as two weeks. During the period of prolongation of the new growth and the formation and receptiveness of the pistillate flower much can happen. The catkins shed pollen when the temperature and atmospheric conditions are normal. Many times the pollen is dispersed before the pistillate flowers are formed.
Cross vs Self-Pollination
There is no assurance that a nut tree which fruits on the average of eight out of ten years will continue to do so in the future. Occasionally trees take on an alternate year bearing habit that could be caused from injury, insect or disease damage, or the relocation of plant food. The nut trees on their own roots should do better than when grafted or budded. The compatability of stock and scion is yet to be worked out and any constriction at the union may alter the fruiting habits.
The possible sources of pollen for hickory and pecan are from self-fertile trees, seedlings, and various natural crosses that may or may not produce edible fruit. The walnut family, which includes the black and Persian or Carpathian walnut; butternut and Asiatic nut (heartnut) have been used as pollinizers on the Persian walnut with some success. The butternut is the first to shed pollen in Indiana with the catkins dropping, in some years, by late April and the first week in May. Some years the black walnut has produced the peak pollen from May 5th to 12th but during the spring of 1953 the Thomas, Stabler, Rowher, Ohio and Stambaugh dropped the pollen from May 18th to 22nd. The Asiatic walnuts were in full bloom on May 14th and 15th. The above dates do not correspond to observations of other years, except for the butternut. The pistillate flowers on the Persian walnuts were fully opened by May 16th. The catkins of the Persian trees had dried by May 12th. Catkins from the Asiatic walnuts were kept fresh and distributed throughout two Persian walnut trees and by mid-afternoon a heavy rain came. On May 18th a few catkins were again removed from the Asiatic walnut and only enough for one Persian walnut tree were found and hung in the tree. The first tree has no fruit while the second tree has a fair crop in the making.
A letter from H. F. Stoke, Chairman of the Survey Committee on the blossoming dates of the Persian walnut said: "Payne, Lancaster and Broadview staminate flowers were out on April 9, 10 and 11. The pistillate flowers of McKinster, Caesar and Crath #1 were receptive on April 11, 10 and 10." The above dates were over a month before spring came to Indiana. Whether or not the Stoke varieties in Virginia would do the same in Indiana or elsewhere is still the problem.
The black walnut varieties mentioned previously set very few fruits at Lafayette this year while a promising new variety, Sol, from Ferd Bolten, Linton, Indiana, has a full crop, and has been a consistent producer for the past several years.
How Many Pounds per Tree
Throughout the Middle West the elm, native chestnut and some of the oaks are dying from disease troubles. The homemaker wants to plant a tree that will provide shade, fit well in the landscaping of the home, be a clean tree and yet be fruitful and bear early.
The age of the tree and the growth has much to do with production. Some pecan varieties have produced several hundred pounds per tree and the same for black walnuts with hickory, butternut and chestnut in smaller quantities. There are four Persian walnut trees growing in Franklin, Indiana, that are 20 years old and have fruited continuously for the past 10 years. The trees were seedlings, two of which are very promising for distribution. Tree #1 produces an average of 10 pounds; tree #2, 15 pounds; #3, about 40 pounds and #4, 100 pounds. Good pollination under common growing conditions of the Midwest and a good variety acclimated for general planting will no doubt make a host of good friends and a wonderful contribution from the members of the N.N.G.A.
Rootstocks for the Walnut in France
J. C. MCDANIEL
This is a translation, by Dr. R. T. Dunstan, of the section on "Rootstocks" in Chapter XI of Les Noyers, by two Doctors of Pharmacy, P. Peyre and E. Lancosme. This 447 page book with 140 figures was published in 1942 by Jouve et Cie, 15, rue Racine, Paris, and is a very complete treatise on the subject of walnuts.
The French experience with the eastern black walnut and the related Arizona walnut as rootstocks is interesting, as is the discussion of one method of propagation, where dormant whole-root grafts are started in pots under glass. This differs somewhat from the indoor grafting procedures described in our recent Reports by Mr. Stephen Bernath and Dr. Philip Brierley. (Incidentally, Dr. Brierley tells me that he got uniformly good grafts—96 to 100% growing—in his 1953 experiment. The use of growth substance powder did not significantly increase the "take". The controlling factors seem to be the use of healthy scions and rootstocks, followed by high enough temperature and humidity to promote rapid callusing of the grafts.)
The "old Royal Walnut" of the French is, of course, what we call Persian (or English) walnut, and not Luther Burbank's "Royal Hybrid", the unfortunately named cross of two black walnuts, J. nigra x J. hindsii. J. torreyi is a synonym for J. major, the Arizona walnut.
Rootstocks fulfilling two essential conditions should be chosen, those capable of adapting themselves to soil and climate where they are to be planted and of resisting diseases that may attack them under unsanitary conditions or under too intense cultivation. Among the numerous varieties tested, two deserve attention as choice rootstocks, one native, the other American = J. regia and J. nigra.
J. regia, our old Royal Walnut, so common in France, is excellent when planted in new, light and fertile soils, preferably clay-lime or clay-silicon.
But as the roots are very spreading it is important to stir the soil well but slightly and avoid deep plowing, for it is well known that through accidental injury to the roots the various "armillaria" enter the trees to develop the "pourridie" or "pus disease", or "circle disease". It is better, then, to use a rootstock immune to this malady so wide-spread among our native walnuts.
J. nigra enjoys this happy advantage of offering no foothold to this parasite, so harmful to its sister species. It accommodates itself well in many soils in which J. regia will grow, even dry and gravelly, but prefers soils which are fresh, open, rich, and especially, deep. Its roots are long and vertical and their development stops in contact with an impermeable layer of soil.
It produces specimens magnificent in height and rapidity of growth. Color of bark differs, though diameter of tree is more or less the same. This slight objection may be easily avoided by grafting regia on nigra at ground-level when wood is well matured and in mild weather.
Proof that this species of walnut is resistant to "pourridie" was given in a report to members of the Congress of Grenoble in 1936 by Mr. Bourne of Saint Marcelin. "At Blache de Vinay, we are told, some black walnuts, planted more than thirty years ago in an infested field, have shown full resistance. One tree, grafted at ground-level and planted too deep, was infected many years ago by the "pus" above the graft on the J. regia part. The diseased part was treated as was the custom then, with sulphuric acid, etc. The wound healed and the rootstock remained absolutely clean. A photo by Mr. Roy, Director of Agricultural Services at Isere, establishes this absolute proof.
Other varieties of walnut have been tested as rootstocks—cinerea, cordiformis, and Siebodiana, but only the first seems to have given any satisfactory results.
Reporter Bourne concludes, "The primary purpose of our research on rootstocks will be to obtain a hybrid of regia x nigra that will combine the resistance of nigra to the "pourridie" and regia's habit of vegetating late in spring.
By virtue of the ability of the female element to transmit its rusticity and vegetative form it seems, a priori, that we shall get a good rootstock by crossing nigra as mother by Franquette (sic) and then if need be, by backcrossing to Franquette in the second generation.
There exists a 4th type of walnut graft, dating from 1880, which if done intelligently, permits the rapid multiplication of the walnut—the root graft.
In a short but very interesting report to the Nut Congress of Grenoble in October, 1936 by Mr. Leon Treyves, and very kindly sent on to us, the author says, "This procedure, devised by my family around 1880, consists of grafting on one year old roots, branches from selected, vigorous trees, either by cleft or English grafts, whichever gives best fit of scion (which is generally smaller than root) and stock. Graft is then tied with raffia and waxed to avoid all contact with air and placed in a moderately heated frame. After a month of this treatment the graft has taken. Then it is gradually accustomed to open air and the frame is removed. In the fall or the following spring the graft may be planted in its permanent location or in nursery row.
This system presents numerous advantages:
1. Rapidity, since the plants can be grafted after one year, instead of three or four.
2. Economy of time and expense, since considerable numbers of grafts can be made rapidly and in limited space.
3. More rapid development of growth and fruiting. Saplings of 1 to 2 meters planted in winter of '28-'29 measured in October '36 25-27 cm. in circumference at one meter from ground. Trees two and three years old, still in nursery, are bearing one to two normally developed fruits.
The author indicates that he uses nigra for stocks, "since that is the only one that has proved its adaptation to grafting and its resistance to the "pus disease"."
At the time he gave his paper in '36 Mr. Treyves announced that he was continuing his grafting experiments on J. Sieboldiana, cordiformis and torreyi. [J. torreyi = J. major—J. C. McDaniel.]
Mr. Treyves, whom we cannot thank too much for his favor, was kind enough to set forth the preliminary techniques of his method of root-grafting. We give a resume of them here.
1. Preparation. Plant nuts well-spaced in rows in good soil, convenient to irrigation, if needed. Clean nuts of good quality, previously stratified, should be planted in winter. Plants are lifted before the following spring and heeled in. For scions wood of 7-8 cm. is cut from young, healthy and vigorous trees and passed to the grafter at the same time as the roots, which have been previously lifted, washed and cut off at the crown or a little below. Scion, bevelled, is set either in English or cleft graft, tied with raffia or with a numbered wool strip, waxed and potted in rich but light soil, moderately firmed around roots. Pots are then set in some homogeneous material (waste tan-bark or sawdust) and left in a moderately heated bed.
2. Care. Watering. Temperature of beds should be kept constant around grafts and they should be watered every other day. Of course, grass and mold should be prevented.
As soon as grafts begin to grow (usually around 15 days) the pots are gradually removed from sawdust, and when plants have made 15-20 cm. of growth (after 30-40 days) they are slowly hardened to air and sun, replanted in well-shaded beds, properly watered and cared for until they are set in nursery row.
3. Planting in nursery. The following spring they are set 60 cm. apart in nursery rows 1 m. apart in well-manured and well-prepared plots. Usual care during growth. With the 2nd year plants attain 1-1/4-1-1/2 m. and it is not uncommon to discover a nut. The 3rd year they make 2-1/2 m. at least with 8-12 cm. of girth and are ready for transplanting to permanent site.
4. Soils and situations. Mr. Treyves tells us that the walnut plantings in "lower Gresivuaudan" are on old alluvium of the Isere Valley and in limy marl soils of the upper slopes. A little farther away in Savoy, the walnut is vigorous in Jurassic or clay limestone soils. The same is true in Dordogne, in Correze, and in the Lot, where soils are of similar origin.
Walnuts are found at an average altitude of 600 m. but grow up to 1200 m. in Savoy, and particularly in Switzerland.
The best exposures are SW, W, and SE, sunny slopes, well protected from the north wind and late frosts.
Mr. Treyves has personally some plantings of walnut in Sologne, (where calcareous soils are lacking) and in Champagne, where the soils lack lime. He has noted that these trees grow and fruit normally.
Cultivation. It is important to keep soil around isolated trees well stirred and to increase the area of cultivation as the rootspread increases.
5. Rootstocks. For the present the plants chosen for stocks have come from nigra, the only one that has proved itself in the matter of "take". It does well in moist soils.
Mr. Treyves has personally tried to graft Mayette and Franquette on Torreyi. He has found the "take" and the union perfect. But even though vegetation is promising we must wait 22 years for a full test.
He proposes to lest all the "rootstocks placed at his disposal in order to acclimatize the good French varieties to all the soils which suit these stocks. Grafting on J. Torreyi will be useful to a [sera utile a un] stock that grows in dry soil, like nigra.
"But that is a matter we shall have to examine again in ten years, first as regards vegetation and then in 20 years as concerns fruit production."
Since these experiments date from '36 at the time of the Grenoble Congress we have only 13 years to wait to learn what sort of fruit these trees will bear and only 5 to see how they behave vegetatively.
It remains, then, only to wish "good luck" to our kind and devoted correspondent and to thank him for his valuable documentation.
Pictorial Record of Grafting at Climax, Michigan
W. M. BECKERT, Jackson, Mich.
Top-working black walnuts to Persian Walnuts has long been practiced by various members of this organization. It is hoped by this series of Kodachrome slides that a record of such top-working by one of our members would be of interest and also show the details of just how the work is done under actual field conditions.
Mr. Gilbert Becker, of Climax, Michigan, has been quite successful in top-working black walnuts. Needless to say, these pictures were taken to show how an expert goes about grafting black walnuts. Mr. Becker was contacted as to when he would do his grafting and he mentioned that on May 80, 1953, he would be top-working his stock. Plans were made to be present on that date and we were fortunate in having bright weather for taking the pictures.
The first two slides show Mr. Becker removing the scionwood from his storage pit, selecting the scions and preparing to go out to do the grafting. On the way to the trees that were to be grafted, the pictures for the next two slides were taken to show the stage of leaf development and the length of the catkins of the Thomas Black Walnut, so members in other sections of the country can see how far out in leaf the Thomas variety was when the grafting was done.
The following series of slides show how Mr. Becker top-works the black walnuts.
First, removing that portion of the stock, note he used a pruning saw, makes a cut at the point where he wants to graft. He uses the bark slit method. The scion is shaped by one stroke of the grafting knife; a long slanting cut is made and the scion inserted in the stock. Just prior to placing the scion, the bark of the stock is slit, two cuts with the point of the knife, approximate width of the scion and down along the bark to the length the scion is to be inserted, then the scion is placed. The next step is to cut off the little sliver of bark which is pushed out, at the point where it does not contact the scion. In this tree, two scions were placed, the scions being wrapped tightly with waxed muslin which was prepared beforehand, using strips about one-half inch wide. Enough was used to firmly bind the scions to the stock. Please note that a small piece of wax muslin was placed on the inside of the scion to prevent the wax from going down between the scion and stock. The final step is waxing the scion and brushing with hot wax, in order to prevent the scion from drying out; to provide shade, Mr. Becker, in this case, used grass and made a hood over the scion, tying it with string.
The following slides show the same procedure of grafting other trees. You will note in one case he has climbed up into the branches of the tree. To shade the scions, he used aluminum foil, folded around the scion and tied with a rubber grafting strip. In all these pictures the scions used were Colby.
Mr. Becker is very adept, quick, and does the grafting so that it actually seems effortless. His technique is so fast, there is very little chance of the scion drying out before it is placed.
On July 26th, I returned to Climax and the grafts were successful, as you can see by the following series. The one failure was the first tree that was grafted, and which had the grass for shading of the scion.
Rock Phosphate for Nut Trees
HARRY P. BURGART, Union City, Mich.
My soil is of the sandy type and I have to watch the mineral content rather closely for nitrogen and phosphate deficiencies. Winter-killing of one year black walnut and pecan seedlings is serious during seasons when our winters are less severe than usual and during winters when we had had plenty of snow cover for protection. This worried me a great deal and I decided there must be a deficiency. Soil tests repeatedly showed a lack of phosphate.
I applied ground rock phosphate to my larger bearing English walnut trees and there has not been the least sign of winter injury since.
Many of my smaller nut trees have been bearing earlier for me since I have been using the phosphate. Customers who come here often remark at the way some of my little grafted trees are bearing crops and I tell them that I believe in keeping plenty of phosphate in the soil for root growth and nut production.
I am writing this brief article thinking that it might help solve the problems of other nut growers who have repeatedly been having trouble with winter-killing of their Carpathian, or English walnut trees. Phosphate seems to prevent a late sappy-condition from causing winter injury.
I prefer to apply the phosphate and nitrogen early in April or early May. Fall applications of any kind of fertilizer are apt to cause winter injury. I usually scatter the rock phosphate around the trees using about four handfuls around a first year tree. Then I turn over the sod bottom with a shovel, which puts the phosphate down where the roots can get it. I use the phosphate around all the young trees we set out and seldom lose a tree as the phosphate encourages the starting of new feeder roots on the nut trees.
A Report From Southern Minnesota
R. E. HODGSON, University of Minnesota, Southern School and Experiment Station, Waseca, Minn.
We have 20 odd Carpathian walnut trees growing from nuts planted about 1931. So far, I have never seen a flower on any of them. They grow up 6 or 8 feet in a year and that seems to be their difficulty. They do not stop growing in time to harden off before cold weather comes. I think a lot of the winter killing is also due to sun scald which would indicate an inability to retain dormancy during a January thaw. Some of the trees have lived through two winters with only minor damage and then when the right conditions come along, they are killed to the ground. Wrapping the trunks with aluminum foil has not solved the problem. I have purchased one or two grafted trees which were recommended as more hardy but so far they have had the same experience as the one I grew from nuts.
Black walnut and hickory do well here and I have a hiccan perhaps 20 feet tall but it has never borne any nuts. Chinese chestnuts are not entirely hardy and grow very slowly. This year I set out about 20 American chestnuts from Minnesota grown seed and I hope that we are far enough from other trees of this variety to escape the blight. Tree growing is just a hobby and lately there has been very little time for hobbies.
Report for 1953
ARTHUR HARMOUNT GRAVES and HANS NIENSTAEDT, The Connecticut Agricultural Experiment Station, New Haven, Connecticut
The chief aim of this breeding work, which has been carried on now without interruption since 1930, is to develop a tall timber type of chestnut by breeding the American species with the blight resistant but comparatively low-growing Japanese and Chinese chestnuts, Castanea crenata and C. mollissima, respectively. Practically all trees of our valuable American chestnut of any appreciable size have now been killed to the ground by the blight fungus, Endothia parasitica. Shoots arising from the base of the old stumps often live long enough to bear pollen, and this we have lately been forced to use in our breeding work with the disadvantage that we can not know definitely the nature of the genotype of the pollen parent. American pollen from a good phenotype near Washington, D. C., was kindly furnished us in the early 30's by the then Office of Forest Pathology of the U.S.D.A., and this stock is now incorporated with our older Japanese-American and Chinese-American hybrids.
As indicated in the following pages, we are not neglecting the nut-bearing potentialities of the chestnut tree.
Weather Conditions in 1953
The disastrous ice storm of the 9th and 10th of January caused slight damage to some of the Chinese trees. Their numerous, more or less horizontal branches and characteristically brittle wood make them prone to damage of this sort; nevertheless, only a few branches were lost. After a comparatively warm February, the warmest since 1925, March brought us more rain than for any March in the 81 years records have been kept—a total of 10.78 inches. This was all to the good, as later events proved. Because of the preceding warm February the ground was for the most part unfrozen, so that, instead of running off, the water was largely absorbed in the soil, and thus added to the water table. The precipitation of April was again heavy—5.6 inches—the normal per month for this area being about 3-1/2 inches. After an unusually good growing season in May, June and July, about the middle of August a long drought of nearly 10 weeks duration commenced. The conditions were similar to those in 1952, except that in that year the drought began later, in October. However, the large amount of water in the soil from the spring rains prevented serious consequences, just as in 1952 the heavy rainfall in August and the normal one in September mitigated any serious results from the later drought of that year.
 Weather records are taken from the monthly reports of the municipal airport at New Haven, Conn., and are compared with the New York City records for the same period, kept by the U. S. Weather Bureau at 17 Battery Place, New York City.
Hybrids of 1953
As in former years we continued the formation of hybrids of the combination CxJxA which has to date given the most resistant individuals and the best timber form. 277 hybrid nuts of this combination were obtained by crossing JA with C, and C with JA. JAxJ crossed with C yielded 25 nuts. CJA crossed with pollen from the Roxbury Americans gave 20 nuts. The Chinese-American hybrids are also promising both in form and in blight resistance. By crossing these with American pollen from Thomaston, Conn., and from Clinton Corners, N. Y., we secured 48 nuts. CA crossed with a good native American in Thomaston, Conn., resulted in 30 nuts, and the same combination using an American in Newfoundland, N. J., produced 9 nuts. The total number of nuts derived from all crosses was 504, a much smaller figure than that for the two preceding years. The reason for this is that considerable time was consumed in experiments designed to determine the length of the receptive period in the pistils.
 C = Chinese, J = Japanese, A = American chestnut.
The 1953 nut production (Table I) compared well with last year's. The total yields were as good as, or better than, the 1952 crop and the average weight per nut was not significantly lower than in 1952. Apparently the late summer and fall drought had no effect on nut yields and average weights. Obviously we have the warm winter and abundant early rains to thank for this situation.
Table I. Natural Yield of Nuts (open pollinations) From Sample Trees.
—————————————————————————————————————— Total yield Av. weight per Approximate Age in Species Location in lbs. nut in grams no. of nuts years 1952 1953 1952 1953 per lb.[A] —————————————————————————————————————— 23 C.crenta 13-2 27.5 43.3 14.5 14.0 32 27 C.mollissima 1-3 22.2 20.8 10.6 10.5 43 27 C.mollissima 1-9 28.2 26.2 9.9 9.7 46 27 C.mollissima 1-15 6.8[B] 20.6 12.9 11.7 39 —————————————————————————————————————— A. based on the 1953 weights B. a considerable part of crop lost before it was collected
Fig 1. gives a fair idea of the extremes in size of the Japanese chestnut. Since the smaller size is probably close to that of the wild chestnut in Japan, the figure illustrates what has been done by the centuries of selection and cultivation that the chestnut has undergone in Japan.
Anent the large nuts in the photograph, which weigh about an ounce apiece or about 28 g. (compare figures in table I), Mr. Ferguson, Instructor at the Long Island Agricultural and Technical Institute, through whom we received the nuts, states that "the nuts of the seedlings from the tree do not average better than half the size of those of the parent tree." This illustrates the fact, now well known, that the chestnut tree is self sterile. Nuts are always (with exceptions) a result of fertilization of the flowers with the pollen from another tree.
We should like to reproduce this tree in our plantations, but the only way it can be done is by grafting scions of it on to some other, preferably Japanese, stock, or by rooting cuttings from it—a method which we still have not been able to accomplish readily.
Moll-Seg, or Chinese Prolific
In the report of the senior writer for 1934 (Brooklyn Botanic Garden Record 24:62) it was stated: "In our form of the Chinese chestnut only one, if any, bur appears at the base of the flowering branch. The dwarf species, C. seguini, from eastern and central China, on the other hand, is most prolific; and in addition, blooms from June to October. It will be seen that crosses of these two species may produce valuable breeding stock." As a result of this cross, made in 1934, we obtained seven nuts, and from these nuts we have today, nineteen years later, four trees, three of which have shown marked blight resistance. One of these three is much larger, partaking more in its stature and form of the character of its Chinese parent, and in contrast to the latter, bears burs and nuts in profusion, usually clustered at the ends of the branches. (Fig. 2). The nuts are small but of good flavor. It is a good nut tree, not suitable for timber. However, as we stated in our 1951-2 report, it is subject to considerable twig blight, caused by the attacks of the weak parasite, Cryptodiaporthe castanea (Tul.) Wehmeyer, and this is due apparently to the influence of its tender parent, the Seguin chestnut, which habitually dies back in the winter. The parasite easily enters the dying ends of the twigs. We should like to see this tree tried out in a warmer climate—Georgia, Florida, Alabama, etc. Possibly it might prove adaptable to a southern European environment.
 Systematic descriptions of this and other valuable chestnut hybrids are being prepared for publication.
Pollen Receptivity of Female Flowers
Chestnut is monecious. The flowers are borne on the present year's growth in long catkins. These are of two distinct types; near the base of the flowering branch they consist of male flowers only. The catkins near the apex, on the other hand, are bisexual; pistillate flowers are found, solitary or in clusters of two or three, near the base of this type of catkin. The remainder of the catkin bears male flowers similar to those on the all-male catkins.
The unisexual male catkins are the first to start flowering and not until two to three weeks later will the male flowers of the bisexual catkins be in full bloom. Normally, the pistillate flowers will reach full development sometime between these two periods of pollen shedding.
The Length of the Receptivity Period.—During the summer of 1953 an experiment was conducted to determine more definitely when the pistils became receptive and how long they remain in this condition. Two Chinese, two Japanese and two hybrid chestnuts of the combination (Jap. x C. pumila) x Jap., the so-called S8xJ, were used as the females in the study. Emasculation and bagging was done at the beginning of anthesis, that is, when the first unisexual male catkins began to shed pollen. Three different pollen sources were used on each female parent; they were of the same species or hybrid combination as the female. The following diagram shows the pollination schedule used.
Pollen source Time of pollination in days No. after beginning of anthesis 5 9 13 17 22 ———————————————————————- 1 X X X 2 X X X 3 X X X
For example, the Chinese female trees were pollinated with pollen from three other Chinese trees (in the diagram "Pollen source No. 1, 2 and 3), which open their anthers on successively later dates. This pollination schedule was used to avoid prolonged storing of the pollen.
To carry on pollination the bags are removed and the pollen-bearing catkins are brushed lightly over the stigmas several times, one or more fresh catkins being used in each bag. These catkins are left in the bag. The bags are then replaced and permanently removed when danger of outcrossing is eliminated, in this case 10-14 days after the last pollination.
The number of nuts collected at the time of harvesting compared with the number of female flowers pollinated was taken as a measure of how successful the pollinations were.
The results showed that five days after the commencement of anthesis a high proportion of the female flowers is receptive. The Japanese and hybrid trees have a definite peak of the period of receptivity between 9 and 17 days after anthesis begins; thereafter, receptivity drops off sharply. The data from the Chinese trees indicated that the period of maximum receptivity is longer than in the Japanese and hybrid chestnuts tested. They maintained full receptivity on the 22nd day after the beginning of anthesis.
It is commonly believed that bagging as well as emasculation may seriously affect the yield from controlled pollination. This is not always the case. One of the Japanese trees and one hybrid tree (S8 x J) yielded fully as many nuts from controlled (under best conditions) as from open pollination. On all other trees the effect of bagging was more or less adverse.
The Effect of Emasculation on Nut Yield
Emasculation involves the removal of the unisexual male catkins and the male part of the bisexual catkins. In the course of the controlled pollination work it has often been found that the female flowers drop off in the bag before the burs start to develop. This has especially been encountered in Japanese x American hybrids and back-crosses. It was thought that this perhaps was due to injuries resulting from emasculation. The following small experiment was carried out in order to determine if this was actually true.
A Japanese x American and a Japanese x (Japanese x American) hybrid were used as the female parents. On these trees some flowering branches were bagged which had been emasculated normally, on other branches only the unisexual catkins were removed, while the bisexual catkins were left intact. Some branches were bagged without any emasculation, and some flowering branches were just tagged. The number of female flowers was counted in all cases. Pollinations were performed 3 times, that is, were repeated on the third and fifth day after the first pollination. This is the procedure ordinarily used for our controlled pollinations. Chinese pollen was used on both trees. Nut set expressed as per cent of the number of pollinated flowers, times three, (because ordinarily there are 3 nuts in every bur) was taken as a measure of how successful the pollinations had been. The results are shown in Table 2.
Table II. The Effect of Emasculation on Nut Yield
———————————————————————————————————————————— Type of Treatment No. of [Symbol: female]'s at Nut set as time of first expressed in % pollination of [Symbol: female]'s at time of 1st pollination x3 [Symbol: female] parent [Symbol: female] parent 4-4 7-4 4-4 7-4 (JxA) (JxJA) (JxA) (JxJA) ———————————————————————————————————————————— Normal emasculation 39 17 29.1 13.7 Only unisexual catkins removed 23 19 14.5 0.0 Not emasculated, but pollinated 28 18 25.0 3.7 Not emasculated, } not pollinated } Control 28 25 1.2 0.0 Not bagged, branches tagged, open pollinated 26 23 44.9 17.4 ————————————————————————————————————————————
Bagging apparently was partly injurious on these two trees and caused some decrease in nut yield. There is, however, no evidence that emasculation in itself causes a decreased nut yield, rather it appears to be somewhat beneficial if we are to judge from the results of this experiment. At least, one would be justified in concluding that any harmful effect is negligible. Completely emasculated flowers yielded 29.1 and 13.7 per cent as compared to 14.5 and 0.0 per cent where only unisexual male catkins were removed, and 25.0 and 3.7 per cent where no emasculation was done. The controls which were not emasculated and not hand pollinated, show that the trees are practically completely self sterile; only an occasional nut is set from self-fertilization.
In vegetative propagation the tree breeder has a very important tool. For instance, if a number of desirable phenotypes have been selected in the forest, they can be propagated vegetatively and planted under uniform conditions where it will be possible to "estimate" their genotype, without the time-consuming progeny testing. Trees propagated vegetatively from old mature trees usually will start flowering very soon after they become established; thus the necessity of doing pollination work in very large trees can be eliminated. Furthermore, it enables the tree breeders to maintain trees of a desirable genotype unaltered for an indefinite length of time without first establishing pure lines through inbreeding. Finally, it may be possible to make valuable individuals available to the forest owners for field planting if they can be propagated vegetatively in large enough numbers at low cost.
Compared to propagation by grafting, the rooting of cuttings is both simpler and cheaper, if it can be done. Chestnut cuttings are, unfortunately, very difficult to root. In the past six years numerous experiments have been conducted in order to find a way to root the various chestnut species. We have tried to root dormant, as well as greenwood, cuttings, the conventional twig cuttings as well as leaf-bud cuttings; numerous hormone treatments using several different hormones in solution and as powders, over a wide range of concentrations, have been tried; a special chamber in which an automatic atomizer nozzle sprays the cuttings intermittently has been used. Results have always been poor. Dormant cuttings have broken dormancy, sent out new leaves, formed an abundance of callus on the basal end, but failed to develop any roots, and finally after several months have died. Greenwood cuttings also have failed to develop roots in almost all cases. The best results have been obtained with leaf-bud cuttings. In some cases 10 to 20 per cent have rooted; here, however, the difficulty has been the failure of the bud to break dormancy and start growth, and all the rooted cuttings have eventually died.
The rooting by airlayering has been tried in a few cases. Airlayering is the rooting of twigs while they are still attached to the tree. Some distance from the terminal end of the twig an oblique cut is made, or the bark is removed around the twig for about 3/4". The cut or ringed area is treated with a hormone powder, wrapped in sphagnum moss and covered with a wrapping of polyethelene. Attempts to root twigs on older trees by this method have so far failed. Recently successful rooting of twigs on young seedlings by airlayering has been reported from Spain, and from France comes the report that stooling of young seedlings is highly successful. In the stooling method the young plants are cut off a short distance above the ground level. As new shoots grow out, their basal ends are gradually covered with soil until a 5-6" mound has been formed. Left in this manner they may develop their own root system and can eventually be detached from the mother root. That the rooting of young seedling material should be possible, while that from older trees will not root, is not unusual. It is generally accepted that the younger the tree from which the cuttings are taken, the easier the cuttings are to root. Experiments along these lines are planned for 1954.
Cooperative Hybrid Chestnut Plantations
In last year's report we described our hybrid test plots established in cooperation with the U.S.D.A., Bureau of Plant Industry, Division of Forest Pathology.
On March 18, 1953 a new plantation was started at Grafton, West Virginia. As usual, we furnished 50 plants for this test plot.
From the reports from Dr. J. D. Diller, of the then Division of Forest Pathology, our hybrids so far have shown a promising performance, although their average growth rate so far is slightly slower than that of the U.S.D.A. hybrids and straight Chinese chestnut. From the standpoint of blight resistance and growth habit they are at least equal to the two other sources and may be slightly better; however, it is still too early to make any definite evaluation of the results.
The most damaging insect pests in the Sleeping Giant Plantation are the spring canker worms, the mites (Paratetranychus bicolor), Japanese beetles and the chestnut weevils.
A spraying schedule has now been worked out which keeps these pests under control:
1. Dormant spray with "Scalecide" in middle April against the canker worms and mites.
2. Two applications of "Aramite" (6-7 lbs. per acre) in the middle and toward the end of June. These sprayings have given good control against mites. Where the outbreak is very severe it may be necessary to spray with "Aramite" also in July and again in August.
3. Spraying with DDT in middle August and the first week in September has controlled the weevils successfully.
In concluding this report we desire to express our thanks to the many interested persons who have contributed pollen, nuts and/or scions to further this project.
Dr. W. C. Deming
On November 17th, 1910, twelve dreamers met in the Botanical Museum, Bronx Park, New York City, to form an organization of nut growers in the north. It was largely an organizational meeting. No papers were read, but some solid foundations were laid. Dr. W. C. Deming served as temporary chairman of the meeting and, fortunately for the cause, was then elected as the new body's Secretary-Treasurer, an office which has always called for executive ability and untiring industry.
This election paid off. At the second meeting, held at the New York State College of Agriculture, in Ithaca, it appeared that the new Secretary had communicated with a large number of leading nurserymen, with national and State horticulturists and with others. It was reported at this meeting that only two nurserymen had accepted the invitation to attend. "So", reported Secretary Deming, "evidently the others do not think the northern nut grower is one whose acquaintance is worth cultivating. We hope to convince them to the contrary."
This was done. At the second meeting, the Association could count sixty members. Professor John Craig, of Cornell, in noting this growth, said, "Dr. Deming has not merely performed the routine duties of the secretary, but he has studied the case and has presented a good many facts not apparent on the surface. It seems to me that this augurs well."
The augury proved prophetic. The Association continued to grow. But without this first intelligent, persistent effort upon the part of. Dr. Deming, it could hardly have survived.
This small bit of history is illustrative of the whole life of Dr. Deming. His deep interest in the purposes and hopes of our Association has never ceased. Upon his own ground he planted, and budded and grafted many nut trees, and has given away the fruits of his labors with a prodigal good will. Deming's Burnham pecan and the Deming Purple black walnut are the only introductions, so far as this writer knows, which bear his name.
Again, some thirty years after the first meeting mentioned above, Dr. Deming thought up and carried through another project which makes the Association repeatedly his debtor, an Index of the first thirty volumes of the Association's Annual Reports. It is a work which saves the conscientious worker in northern nut culture hours and hours of labor.
And now our Dean, the last of the founding fathers, has left us for the Elysian Fields. His gentle, kindly face will be sadly missed by those who knew him, but he lives on in every tree whose planting his labors inspired and in every mind which has been, even unconsciously, his heir.
A letter from Miss Charlotte Deming, a sister, assures us, somewhat touchingly, but happily, of this fact:
"My brother's heart was with and in the work of the Association. He was happy to know of its expansion into such a wide-spread organization, and very proud of having been made its Dean."
Dr. Deming lived a full life. He was a physician of distinction, a graduate of Columbia University's College of Physicians and Surgeons and was retired from the army after World War I with the rank of Major. After graduation from Columbia, he served his internship in a New York hospital, then on the medical staff of the State Immigrant Hospital, Ward's Island. He began private practice in Westchester County, New York and, later, for many years, served as examining physician with the Veterans' Administration in Hartford, Connecticut.
It is interesting to know, as told by his son, Hawthorne, that Mrs. Deming, formerly Imogene Hawthorne, was the youngest granddaughter of the immortal Nathaniel. It is evident that Dr. Deming, both in private life and in his public interests, was a strong believer in the value of good blood-lines.
The Nomenclature of Nut Varieties
GEORGE H. M. LAWRENCE, Bailey Hortorium, Ithaca, N. Y.
This article is intended to introduce to you the International Code of Nomenclature for Cultivated Plants and to point out the ways in which that Code serves the interests and needs of members of the Northern Nut Growers Association.
 The International Code of Nomenclature for Cultivated Plants, formulated and adopted by the International Botanical Congress Committee for the Nomenclature of Cultivated Plants and the International Committee on Horticultural Nomenclature and Registration at the Thirteenth International Horticultural Congress, London, September 1952.
Copies of the full text of the Code are available from the Secretary, American Horticultural Council, Inc., Bailey Hortorium, Cornell University, Ithaca, N. Y., (25c postpaid).
The Code as published by the Royal Horticultural Society is a booklet of about 30 pages, containing an excellent historical introduction by W. T. Stearn, a summary or abridged version of the Code, and the full text. It is of necessity somewhat technical in its phraseology, and in places its jargon is overwhelming. Recently, Dr. John S. L. Gilmour, Director of the Cambridge Botanic Gardens, and formerly Director of the R. H. S. Trial Gardens at Wisley, published a very lucid and down-to-earth interpretation of the principle provisions of the Code. It is reproduced with permission at the conclusion of this introduction.
The questions asked about the Code include,
"What's it got that earlier codes did not have?" "What's new about it?" "How does it affect me?"
There are several answers to the first query, but the most significant is that here for the first time we have a Code that represents the thinking of horticulturists from all leading horticultural centers of the world. I was a member of a committee of thirteen (representing 6 countries), that met for nine days in Stockholm in 1950 to prepare and edit the first international draft of this Code. Those of each nationality had met in their country previously, with their own leaders, and had come to this round-table session with fixed ideas of what they wanted. By mid-evening of the first session it became apparent that the Swedes, the Dutch, the British, and the Americans had sent some of their most persuasive, vocative, and determined countrymen to represent them. The Swiss representative restrained himself admirably until after the initial lines had been drawn. It looked then as if there might be several codes, but before recessing several hours later some concessions had been made, and discussion on the more volatile points had been deferred. The differences of opinion were well founded and held with good reason. Some reflected an unawareness of situations in an unrelated horticultural field, e.g., a nurseryman did not know the problems encountered by the Danes in developing so-called varieties of vegetables, or by the American in producing hybrid-corn—each calling for different provisions in the Code, nor could the rose specialist be expected to comprehend the genetic situations encountered in many types of hybridity. One botanist in the group had no appreciation of the intricacies of problems and situations found when trying to name some complex groups of cultigens. Add to these reasons the fact that most of these men were representatives or spokesmen for larger groups or national organizations "back home" and were not authorized to act independently from earlier decisions by those groups, and one can only marvel that at the end of the 9-day period we came up with a detailed and workable draft accepted unanimously, and which was modified in no major respect at the more recently International Horticultural Congress in London.
The period between the Stockholm meeting and the London Congress was utilized to distribute mimeographed copies of the Stockholm draft to horticultural leaders in all countries, to provide opportunity for suggesting changes and new provisions for the Code, and to hold one committee meeting of international level, at London in November 1951. As a result, the present Code is the first truly international regulating guide that has been produced as an aid to persons concerned with the nomenclature of cultivated plants. The individual who may object to some provision of the Code must remember that its presence in the Code has had the support of scores of specialists, representing no less than 16 nations and that there is no part of the Code that was not acceptable to a majority of the delegates of each nation and to the groups representing them. The significance of this international character of the Code is not to be discounted.
It is only proper at this point to tell you how the U. S. A. was represented at the International Horticultural Congress in London. Practically every country except the United States has a national horticultural organization, comparable in some respects to the Royal Horticultural Society, with which you are surely familiar. This country had none. When the "call" went out for representatives and delegates to the International Horticultural Congress, that for this country was delivered to the agricultural attache at our Embassy in London. It is reported that he referred it to his home office and attended some preliminary meetings in London. The matter was referred to the U. S. Department of Agriculture in Washington and there sat, apparently, for months. In the interim, private communications were flying across the Atlantic in both directions between interested horticulturists and finally the matter was referred by the Honorable Secretary of the Congress direct to American societies of horticulture to ensure that American views and interests would be adequately represented. It boiled down to the United States being represented by those persons who were going to be at the Congress anyway and by men who were not specialists in nomenclatural matters. Appraised of their lot, these persons made every effort to be briefed and informed on as many aspects of the provisions of the proposed Code as possible. As stated later by Dr. S. L. Emsweller (a member of the committee, representing U. S. D. A. and the American Society for Horticultural Science), this situation brought into sharp focus the need in this country for a single horticultural organization of organizations that could serve as authorized in matters at the international level. The American Horticultural Council, to which the Northern Nut Growers Association belongs may become that organization, but only when authorized by its membership.
Many readers may be familiar with earlier codes, as that adopted by the American Pomological Society (which dates from 1847), that by the American Society of Agronomists (formulated in 1917-18), and with a third code adopted at the sessions of the Botanical Congress meeting in Cambridge, England, in 1935. Knowing of the provisions of these codes, you may ask, "What has the new one got that is different?" There are many new features of which the more significant are given below.
Perhaps foremost is the recognition that, for the most part, the so-called varieties of garden plants are not uniform in their behavior. Some are nothing more than transplants of variations found in the wild, such as the Japanese Juglans Sieboldiana var. cordiformis, a population having its own geographic range and distinguished from the typical element of the species by several morphological characters. It is a botanical variety that is cultivated. It is not a product of domestication.
The code distinguishes from this botanical variety those so-called varieties that are the result of domestication, variants that have been produced in cultivation but are not known to occur and perpetuate themselves in the wild, such as Schwedler's maple known as Acer Platanoides var. Schwedleri. Plants of this group, that may be grown from seed and which do show a limited variability, are distinguished from botanical varieties by placing them in a new category called cultivar (a name coined long ago by L. H. Bailey and meaning, a variety from cultivation). The abbreviation for the category is cv. Furthermore, in an effort to differentiate cultivar names from botanical names, it is provided that they be treated as are vernacular or fancy (common) names. That is, that the name be placed in single quotes and not italicized e.g., Acer Platanoides cv. 'Schwedleri'.
A third category is that of clone. A clone is an individual propagated not from seeds but by asexual means, as by grafting, budding, cuttings, etc. Most so-called varieties of nuts are clones. A clone may be selected from a species population, from a botanical variety, from a cultivar, or from anyone of several types of hybrid complexes. It may appear as a mutant of another clone. The name for it may, where there is need for precision, be attached to the name of the species (or hybrid) from which it was selected, as Corylus Avellana cl. 'DuChilly' or reduced to Corylus cl. 'DuChilly.'
For the hybridizer naming and introducing new hybrids to cultivation, the Code is more helpful than any previous set of rules and the needs of hybridizers of various groups have been considered. Many examples illustrating application of each provision are given in the unabridged version.
The person naming plants will find much helpful guidance with regard to the selection of names which should be considered if international usage is to prevail. The Code is just that, a set of dicta provided for guidance by horticulturists throughout the world that there may prevail
a greater uniformity, accuracy, and fixity of names, a lessening of procedures that would lead to confusion and error if adequately supported or widely adopted, and a provision for change and revision.
One section of the code ("C") dealing with Registration might well come within the framework of interest and activity of the Northern Nut Growers Association. This section, which suffers materially by condensation in the abbreviated text that follows, occupies nearly a page in the unabridged edition. It envisages the establishment of an international registering body, with headquarters for different groups located in different countries, e.g., that for tulips in the Netherlands, for rhododendrons in Britain, for roses in the United States, etc. The task of compiling, maintaining, and publishing such a registrar (and rejecting names not in conformance with the Code) will fall in many cases on the special plant societies concerned. When societies for a given group of plants exist in 2 or more countries, they will be expected to collaborate. Insofar as I know the Northern Nut Growers Association has not set up any mechanism for the registration of names given to cultivars, hybrids, and clones of nuts. To do so would be to perform a very real service for your membership, for the industry in this country, and would place the Association in a key spot when the proposal for an international registry is activated. The agitation for this phase of international application of the Code is considerable and is more evident in Europe than here. If the Association takes an active stand in the matter and develops a center of registry of nut names for this continent, it may very well display a quality of initiative and service that will make it pre-eminent on the international level and will cause others to look to it for guidance, information, and leadership.
A careful consideration of this Code is commended to all and those interested in the topic are urged to procure a copy of the booklet giving the unabridged edition and Stearn's excellent historical account of the subject.
The New Code For the Naming of Cultivated Plants
 Reproduced with permission from Journal of the Royal Horticultural Society, vol. 69, pp. 12-21, 1954.
J. S. L. GILMOUR, Chairman of the International Committee on Horticultural Nomenclature and Registration
Anyone who deals in any way with cultivated plants uses plant names. This glimpse of the obvious ought to mean that the appearance of a new Code for the naming of cultivated plants should be a memorable event for all gardeners. I say "ought to mean" advisedly, because there is no doubt that, in the past, Codes of Nomenclature have made little appeal to gardeners, the great majority of whom have been blissfully unaware of their existence. As a consequence, many horticulturists—on hearing of "a new Code"—will, no doubt, raise a respectful (or contemptuous) eyebrow and get on with reading their latest catalogue. The aim of this article is to persuade readers of the Society's JOURNAL, not only that this attitude is against their own interests, but that a good deal of quiet entertainment can be extracted from trying to use plant names correctly—if only the entertainment of putting their neighbour right!
It is true that, hitherto, there has been ample excuse for ignorance. Although Codes for the naming of cultivated plants have existed, in some shape or form, for nearly 100 years, they have been printed in obscure publications, quite inaccessible to ordinary mortals. This excuse no longer holds. The full text, plus a summary, of the new Code can be purchased for one shilling and three pence (post free) from the Society, and, in addition, reference to it has been made in many horticultural and other periodicals. What, then, is the new Code about, how does it affect gardeners, and what should they do about it?
In the first place it is not about the Latin names of wild species or varieties—names like Rhododendron ponticum and Aesculus octandra var. vestita. Whether wild plants are grown in gardens or not, their Latin names are governed by quite a separate Code, devised by botanists for the purpose. It is true, of course, that gardeners have to use Latin names for many of the wild plants that they grow, and equally true, unfortunately, that the frequent changes in these names are a source of annoyance to everyone; but that is quite another story, with which we are not concerned here. At the last International Horticultural Congress steps were taken which we all hope will result, with the cooperation of botanists, in the stabilization of widely used Latin names of cultivated plants.
No, the new Code deals, not with wild species, varieties and hybrids, but with what are commonly called "garden varieties"—namely, forms which have been brought into existence by selection, hybridization, or other similar processes devised by man, and are maintained in cultivation as clones or pure lines by man's care and skill—such plants as Rose 'Peace,' Apple 'Beauty of Bath,' and thousands of others. The distinction between "wild" plants and "garden varieties" is not absolutely clear cut, and in the Code a closer definition is attempted—but for our present purpose the difference is obvious enough.
In the Code, it is recommended that "garden varieties" should technically be called "cultivars." This has been their official name for many years and it is clearly desirable, if the two categories of "wild" and "cultivated" varieties are to be recognized, to have a short and internationally current word for each of them. "Variety" and "cultivar" serve this purpose admirably, but it is not to be expected that all gardeners will make the distinction and adopt the word "cultivar" in ordinary parlance, at any rate immediately. Personally, however, I hope and believe that eventually "cultivar" will find favour. It is a clear and easily understood word and will, I think, prove useful to those gardeners who care for accuracy and precision in their craft, and especially to those who have dealings with fellow-gardeners in other countries.
The Code, then, deals with the names of cultivars. It may be helpful, I think, to consider its rules and regulations under three headings: firstly, those of interest to all gardeners who have occasion to write the names of cultivars; secondly, those which are concerned with the coining of new names; and thirdly, those more technical provisions which are of interest primarily to horticulturists studying a particular group and trying to establish what are the correct names for its cultivars.
1. The Writing of Cultivar-Names
The most important point, perhaps, concerning the names of cultivars is that they should not be in Latin, but in any modern language using the so-called Roman alphabet (i.e. the alphabet in which English, French, German, etc., are written). The reason for this is, of course, to distinguish, at a glance, names of cultivars from names of wild varieties, which are in Latin. In the future, Latin names for cultivars will definitely not be allowed by the Code, but we are faced with the fait accompli of hundreds of existing Latin names which have been widely used for many years. For example: the dwarf conifers abound with cultivars called 'nana,' 'prostrata,' 'compacta' and the like, and such names as 'albus,' 'variegatus,' and 'plenus' occur in almost every cultivated genus. It would clearly be foolish to try to alter all these, and the Code accepts such legacies from the past as permanently with us. (As we shall see, however, a distinction is made between the writing of Latin cultivar-names and Latin varietal-names.)
The vast majority, then, of cultivar-names are vernacular or "fancy" names like 'Winston Churchill.' How should the full name of a cultivar be written? The complete and technically correct form, including the Latin name of the species from which the cultivar has been derived, is illustrated in the following example: Sedum spectabile Boreau, cv. 'Brilliant,' but I hasten to add that this lengthy designation is for use only on full-dress occasions! In the example, Sedum is the name of the genus, spectabile the name of the species (technically called the "specific epithet"), Boreau the name of the man who first described the species under that name (technically called "the authority" for the name), cv. the abbreviation of cultivar, and 'Brilliant' the cultivar-name for the particular cultivar concerned. It should be noted (1) that the generic name and specific epithet are printed in italics, (2) that the cultivar-name begins with a capital letter, is printed in ordinary Roman type, and is enclosed in single quotation marks, and (3) that there is no "authority" after the cultivar-name. These three points are important, and apply to the writing of all names of cultivars. If we wish to cut down this rather formidable string of words for every-day use, the authority can be omitted in all except very technical writing. Secondly, the abbreviation cv. can normally be left out, as the vernacular form, single quotes, and Roman type of 'Brilliant' indicate quite clearly that it is a cultivar-name, and not the name of a wild variety. In this shortened form, therefore, the name would read simply:
Sedum spectabile 'Brilliant'
and this is the normal method of writing the names of cultivars.
There are, however, two additional refinements that should be mentioned—apart from the special case of cultivars derived from hybrids, which I will deal with later. The first concerns those Latin cultivar-names which are left over from the past. These should be printed in Roman type and enclosed in single quotes to distinguish them from Latin varietal names; thus one would write Thuja orientalis 'elegantissima,' where 'elegantissima' is a cultivar-name, but Aesculus octandra var. vestita, where vestita is the name of a wild variety.
The second point refers to the omission of any authority after a cultivar-name. Many cultivars are first described in reports of trials, in catalogues, and other anonymous publications; this makes the quoting of an authority impractical, but there is provision in the Code for writing the raiser's or introducer's name in brackets after the cultivar-name if so desired, thus: Weigela 'Avalanche' (Lemoine).
2. Naming New Cultivars
Let us suppose that a nurseryman, park superintendent, or amateur gardener has just flowered a batch of seedlings of, say, Helenium, and that he spots one as being of a new type and worthy of propagation. In due course he shows the plant at a fortnightly show, under a number, and an Award of Merit is given to it. He must now find a cultivar-name for his new plant. His first problem, of course, is to choose a name that has not been used before in the genus Helenium. If he picks on a very unusual personal name he can be fairly certain that he is the first to use it. If, however, he prefers a more general name, like 'Innocence' or 'Venus,' there is a danger that it has been used before. If there existed a registration authority for Helenium names, as there does, for example, for names of Daffodils, he could, of course, consult this authority, but in its absence he must do his best to comb the likely literature—for example the Index to this JOURNAL, nurserymen's catalogues, etc.—and to assure himself that his chosen name has not already been used. His next step is to make certain that the name is in accordance with the best practice for coining such names. Here is where the Code will help him. In it he will find (under Section F) a series of rules for his guidance, based on the accumulated experience of horticulturists of many nations. I will not repeat these rules here—they can be read in the Code—but perhaps the most important, apart from the rule already quoted that the name must not be in Latin, is that it should be short (not more than two words), should avoid forms of address liable to be confused (e.g. Mr., Mrs. and Miss) and, as far as possible, should be easily pronounceable by all nationalities. As the Code says, 'Centenaire de Rozain-Bourcharlat,' 'Diplomagartenbauinspektor,' and 'Eldwyth Cholmondeley' are not looked upon with favour as cultivar-names! Having chosen a name, it is essential to ensure that it is published, together with an adequate description, since the Code does not recognize names that are not published, or are published with no description. The Code lays down what is meant by publication, and by adequate description. The names of plants which receive an Award at Vincent Square are automatically published, with a description, in this JOURNAL, but for other methods of publication the Code should be consulted.
The naming of cultivars derived from crosses between two or more different species, belonging to the same or different genera, involves rather special problems. By "derived from" I mean not only the first generation from a species cross, but all subsequent generations and back-crosses with the original parents or with members of the first or later generations. Any cultivar which is the progeny of a species cross, however remote, comes, for the purpose of the Code, under the heading of a hybrid and its naming is subject to definite rules. The full name of a "hybrid cultivar" must be regarded as consisting of three distinct parts: (1) the name of the genus (or "hybrid genus" if a hybrid between two or more genera is concerned); (2) a "collective" name or phrase covering all the progeny resulting from the particular species-cross concerned; and (3) a cultivar-name for the particular form (cultivar) under consideration. In the name Viburnum x bodnantense 'Dawn,' Viburnum is the generic name, x bodnantense is the collective name for all progeny of the cross V. fragans x V. grandiflorum, and 'Dawn' is the cultivar-name for a particular seedling of this parentage. It is essential always to bear in mind these three distinct parts of the name of a garden hybrid, even if, as it often done, one or other of the parts is omitted in actual usage; the three parts broadly correspond, of course, to the generic name, specific epithet, and cultivar-name of a non-hybrid cultivar (see above).
Let us consider these three parts in turn and see what types of name can be used in each part in actual practice—and how this affects the naming of new "hybrid cultivars."
The first part, the generic name, presents no difficulties, except in the case of new hybrids between two or more genera. Names of such "hybrid genera" are usually "manufactured" from a combination of the names of the parent genera (e.g. x Heucherella, from Heuchera and Tiarella); in the case of hybrids between more than two genera, however, where a "combination" name would be unwieldy, it is permissible to make a new name by adding the termination ara to the name of a person connected with the plant concerned (e.g. x Sanderara for a tri-generic orchid hybrid). Before making a new "hybrid generic" name, a botanist should be consulted, as a Latin description in proper, botanical form must be provided. It will have been noticed that a multiplication sign is placed in front of the names of "hybrid genera," but after the generic name in the case of hybrids within a single genus; further details on this point are given later.
The second part of the full name of a hybrid is a more tricky business. It is, as I have said, a collective designation for all the progeny of the particular cross concerned, and it may take one or all of three possible forms:—
(1) If the parentage is known, a bare formula consisting of the names of the parents, in alphabetical order, connected with a multiplication sign, e.g. Lewisia cotyledon x rediviva.
(2) A name in Latin form (corresponding to a non-hybrid specific epithet), preceded by a multiplication sign, e.g. Viburnum x bodnantense.
(3) A vernacular phrase containing the word "hybrid," "cross," "grex" (Latin for flock or group), or other similar word, making evident the collective nature of the phrase, e.g. Lilium 'Bellingham Hybrids.'
Why do we have to have these three different forms for the second part of the full name, and when, to put it briefly, should we use which?
I must admit that practice on this particular point is as yet by no means fixed, and no doubt it will be modified considerably during the next few years, as more horticulturists try to apply the Code to the groups in which they are interested.
In order to understand the alternatives available, it will be helpful, I think, to consider first the third part of the full name, as the use of this, and of the second part, are very closely connected. The third part, as I have said, is a cultivar-name of a particular form of the hybrid concerned, and, in the first place, it is extremely important to realize that every cultivated hybrid that is considered worth naming at all should receive a cultivar-name from the outset of its "career," even if, at the time, only one form is known, or is considered worth naming. To take an actual example, at the time when the new hybrid Viburnum x bodnantense was described in the Botanical Magazine, only one form, or clone, of it had been "put into circulation," and yet that single clone was given a cultivar-name, 'Dawn.' The object of doing this was to be able, in the future, to refer by name to this particular clone and so avoid confusion with any later, and possibly inferior, forms of the same cross that might be produced. In the absence of the name 'Dawn,' less desirable clones could legitimately be passed off under the collective name V. x bodnantense without the acquirer realising that he was not getting the original and superior form.
Bearing in mind, then, the principle that all cultivated hybrids should have a third part, cultivar-name, we can turn again to the use of the various possible designations for the second part listed above. The choice of designations depends, broadly speaking, on convenience, that is to say, on what, in practice, will be found the most useful method of referring to the plants concerned. In principle, of course, every hybrid whose parentage is known has an appropriate formula-designation, and in certain cases such a formula would be sufficient as a second part designation without inventing either a Latin name or a vernacular collective name. For instance, when there are only a very few forms of a particular cross, it might not be considered necessary to be able to refer to the forms collectively, and a second part name would not then be given. For example, Rubus 'Merton Thornless,' when raised, was the only form of the hybrid R. rusticanus inermis x thyrsiger to be put into circulation, and it was not given a second part designation other than the appropriate formula. On the whole, however, it is usually desirable to have a second part, collective designation, rather than a formula only. Whether such designation should be a Latin name or a vernacular phrase, or both, depends on a number of factors which, as I have said, are not yet fully worked out or appreciated. Broadly speaking, if there are a large number of cultivars of a particular cross and these cultivars form a well-marked group, distinct from other hybrid groups in the genus, it is useful to have a vernacular designation for general use, e.g. 'Bellingham Hybrids' for all cultivars of the cross Lilium Humboldtii x pardalinum. This purpose can, however, be equally well served by a Latin name, e.g. Camellia x Williamsii for all cultivars of the cross C. japonica x saluenensis. Whichever method is chosen, two points are of great importance. Firstly, if a Latin name is given, it must be accompanied by a Latin description. Secondly a vernacular designation must contain some such word as Hybrids, Crosses, or the like, to distinguish it from a cultivar-name. The practice, in some groups, of giving "straight" cultivar-names as second part collective designations, followed by "var. so-and-so," is condemned by the Code. Existing names of this kind, however, can easily be brought into line by adding a word such as Hybrids or Grex to the old, second part, cultivar-name, and omitting the "var." thus, Cattleya 'Fabia' var. 'Prince of Wales,' would become C. ('Fabia Grex') 'Prince of Wales' (Grex can he abbreviated to G. if desired). This alteration may seem over-pedantic, but if, in the naming of cultivated hybrids, a clear distinction is not kept between second and third part names, confusion, as I have pointed out, is likely to result.
I will finish this section on the naming of hybrids with one or two additional points on the correct method of writing their names. Here are the full names of three cultivated hybrids:—
Rubus (rusticanus inermis X thyrsiger) 'Merton Thornless.' Camellia X Williamsii 'Donation.' Rose (Hybrid Tea) 'Richmond.'
The following points should be noted:—
(a) If a formula or a vernacular designation is used as a second part name, it should be placed in brackets between the generic name and the cultivar-name.
(b) If a Latin name is used as a second part name, and the hybrid is between plants belonging to the same genus, a multiplication sign should be placed between it and the generic name.
(c) The third part cultivar-name follows directly on the second part name and is placed in single quotes, as for cultivar-names of non-hybrids.
In many contexts it would not be necessary to write the second part name at all, but if it is omitted, the cultivar-name, strictly speaking, should be preceded by a multiplication sign, thus: Camellia X 'Donation,' but it would be no great crime to omit it, except perhaps in technical publications.
3. What Is the "Correct" Name for a Cultivar?
It is a painfully familiar fact that many cultivars are known by more than one name, and that many cultivar-names have been applied to more than one cultivar—although the position is not so bad as it is in the case of botanical names! This multiplication of names is the inevitable result of many people naming many plants over a period of many years. It is a situation which we must accept and do our best to mitigate. The Code has a number of necessarily rather complicated provisions aiming at selecting the correct name for any cultivar. These provisions are important mainly to the comparatively few horticulturists and botanists who take on the unenviable job of sorting out the nomenclature of cultivated plants, though the results of their labours affect us all. The rules are set out fully in the Code, and here I will attempt only to pick out one or two of the more important.
The Code lays down two basic principles; though, as we shall see, these may be modified if undesirable name-changing can be avoided thereby.
(a) No name can be used if it does not conform to the various rules laid down in the Code (including proper publication of the name, with a description).
(b) If there are two or more names that conform with the Code, then the earliest name is the correct one; this is known technically as the principle of priority.
Now, obviously, as happens with botanical names, the strict application of priority might mean that a universally used name—say, Plum 'Victoria'—would have to be given up and replaced by a completely unknown one. This is unthinkable, and, as in the Botanical Code, there are clauses to prevent it happening. With cultivar-names, however, there is a particular complication, which does not apply to botanical names. The latter are all in Latin, whereas cultivar-names may be in many languages. This means that a cultivar, raised in one country under a name acceptable in that country, may be introduced into another country where the original name is quite unpronounceable or otherwise unsuitable. A new name is, of course, immediately invented by the introducer, and clearly, in many cases, it is useless to try to make the second country adopt the earlier, strictly correct, but unsuitable name. The Code, therefore, allows the retention of the second name as what it calls a "commercial synonym." Thus, Rose 'Permanent Wave' is a commercial synonym in the United States for the Rose raised in Holland as 'Mevrouw van Straaten van Nes.' In any formal list of Roses, both names should be given, together with any other commercial synonyms that may exist. The coining of commercial synonyms is not, of course, to be encouraged, and should only be done if the original name is clearly unsuitable for the new country. Frequently names are translated or transliterated when a cultivar is introduced into another country, and such a translation or transliteration is not regarded in the Code as a new name, but as the original name in another form; no difficulty, therefore, arises as to priority in these particular cases.
Perhaps the most important section of the whole Code deals with the Registration of cultivar-names. In certain groups (e.g. Daffodils) international registration schemes already exist, and it is urged that further schemes, covering all important groups of cultivated plants, should be established as soon as possible. The function of such authorities would consist, primarily, of (1) registering new names and ensuring that they are in accordance with the Code, and (2) preparing, and keeping up to date, lists of cultivars in their groups. In addition, the authorities would choose a particular publication as the "starting-point" of the nomenclature in the group (so as to avoid dipping too deeply into the past in search of ever earlier cultivar-names), and would act as arbiters when a decision has to be made between two or more widely used names for the same cultivar. There is no doubt in the minds of those responsible for the Code that the existence of internationally trusted and respected registration authorities would do more than anything else to stabilize and simplify the naming of cultivated plants. It will obviously take some time before authorities can be set up for all—or even the majority—of important groups, but the International Committee is doing its best to push ahead quickly with this very important side of their work.