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DISCLAIMER The articles published in the Annual Reports of the Northern Nut Growers Association are the findings and thoughts solely of the authors and are not to be construed as an endorsement by the Northern Nut Growers Association, its board of directors, or its members. No endorsement is intended for products mentioned, nor is criticism meant for products not mentioned. The laws and recommendations for pesticide application may have changed since the articles were written. It is always the pesticide applicator's responsibility, by law, to read and follow all current label directions for the specific pesticide being used. The discussion of specific nut tree cultivars and of specific techniques to grow nut trees that might have been successful in one area and at a particular time is not a guarantee that similar results will occur elsewhere.
NORTHERN NUT GROWERS ASSOCIATION
REPORT
OF THE PROCEEDINGS AT THE
SECOND ANNUAL MEETING
ITHACA, NEW YORK DECEMBER 14 AND 15, 1911
PRESS OF THE ITHACA JOURNAL ITHACA, NEW YORK 1912
Transcribers' note: The errors listed below have been corrected.
Errata
Page 3, under "Officers" transpose addresses of President and Vice-President. Page 23, line 5, for "Pennsylvania" read "Louisiana." Page 103, line 2, for "Siebold" read "Nebo."
TABLE OF CONTENTS Page
Officers and Committees of the Association 3
Members of the Association 4
Constitution and Rules of the Association 6
Proceedings of the meeting held at Ithaca, New York, Dec. 14th and 15th, 1911 7
Address of Welcome by Professor Craig 7
Secretary's Report of the Meeting for Organization held in New York Nov. 17th, 1910 8
Secretary-Treasurers' Report for the Year 10
Discussion on Juglans Mandshurica 12
President's Address. The Hickories, Robert T. Morris, M. D. 14
Discussion 21
The Chestnut Bark Disease. J. Franklin Collins, Washington, D. C. 37
Discussion 43
Nut Growing in the Northern States. C. A. Reed, Washington, D. C. 49
Discussion 56
The Indiana Pecan. T. P. Littlepage, Washington, D. C. 62
Discussion 74
Executive Session 75
The Bench Root-Grafting of Persian Walnuts and Pecans. C. P. Close, Washington, D. C. 79
Discussion 80
The Hales' Paper Shell Hickory. Henry Hales, Ridgewood, New Jersey 85
Discussion 86
Nut Promotions. W. C. Deming, M. D., New York 89
Some Facts Concerning Pecan Trees for Planting in the North. W. N. Roper, Petersburg, Virginia 92
Discussion 95
The Scolytus Beetle. Prof. G. W. Herrick, Ithaca, New York 96
Discussion 99
The Persian Walnut in California. Prof. E. R. Lake, Washington, D. C. 100
Discussion 102
Is There a Future for Juglans Regia and Hicoria Pecan in New York and New England? Prof. John Craig, Ithaca, N. Y. 106
Resolutions and Executive Session 109
Exhibits 110
Appendix 111
Miscellaneous Notes 111
Report of Committee on Exhibits 111
Prize Nuts 112
Report of the Committee on the Nomenclature of Juglans Mandshurica and the Shellbark Hickories 114
The Hickory Bark Borer. Circular and Correspondence 116
Resolutions of the Pennsylvania Conference on the Chestnut-tree Bark Disease 122
OFFICERS
President Robert T. Morris New York
Vice-President T. P. Littlepage Indiana
Secretary and Treasurer W. C. Deming Westchester, New York City
COMMITTEES
Executive
John Craig C. A. Reed W. N. Roper And the Officers
On Promising Seedlings
T. P. Littlepage C. A. Reed W. C. Deming
On Hybrids
R. T. Morris Henry Hicks C. P. Close
On Membership
W. C. Deming E. R. Lake J. G. Rush W. N. Roper
On Nomenclature
John Craig R. T. Morris W. C. Deming
On Press and Publication
W. N. Roper T. P. Littlepage W. C. Deming
STATE VICE-PRESIDENTS
Connecticut Charles H. Plump West Redding Florida H. Harold Hume Glen St. Mary Georgia G. C. Schempp, Jr. Albany, Route 3 Illinois Dr. F. S. Crocker Chicago Indiana R. L. McCoy Lake, Spencer Co. Louisiana J. F. Jones Jeanerette Maryland C. P. Close Washington, D. C. Massachusetts Bernhard Hoffman Stockbridge Minnesota C. A. Van Duzee St. Paul New Jersey A. B. Malcomson West Orange New York A. C. Pomeroy Lockport Ohio J. H. Dayton Painesville Panama B. F. Womack Canal Zone Pennsylvania J. G. Rush West Willow Virginia W. N. Roper Petersburg
MEMBERS OF THE NORTHERN NUT GROWERS' ASSOCIATION
Abbott, Frederick B., 419 9th St., Brooklyn, N.Y. Barron, Leonard, Editor The Garden Magazine, Garden City, L.I. Benner, Charles, 100 Broadway, New York City. Button, Herbert, Bonnie Brook Farm, Cazenovia, N.Y. Chute, Miss Bessie, 1024 University Ave. S.E., Minneapolis, Minn. Clendenin, Rev. Dr. F. M., Westchester, New York City. Close, Prof. C. P., Expert in Fruit Identification, U. S. Dept. of Agriculture, Washington, D. C. Coleman, H. H., the Northwestern Mutual Life Insurance Co., Newark, N.J. Craig, Prof. John, New York State College of Agriculture, Ithaca, N.Y. Crocker, Dr. F. S., Columbus Memorial Building, Chicago, Ill. Dayton, J. H., Painesville, Ohio. Representing the Storrs & Harrison Company. Deming, Dr. N. L., Litchfield, Conn. Deming, Dr. W. C., Westchester, New York City. Deming, Mrs. W. C., Georgetown, Conn. Dennis, Dr. Frank L., The Colchester, Colorado Springs, Colorado. *Hales, Henry, Ridgewood, N.J. Hicks, Henry, Westbury Station, L.I. Hoffman, Bernhard, Stockbridge, Mass. Holden, E. B., Hilton, N.Y. Holmes, J. A., 127 Eddy St., Ithaca, N.Y. Hume, H. Harold, Glen St. Mary, Fla. Hungerford, Newman, 45 Prospect St., Hartford, Conn. +Huntington, A. M., 15 W. 81st St., New York City. James, Dr. W. B., 17 W. 54th St., New York City. Jessup, Miss Maud M., 440 (40) Thomas St., Grand Rapids, Mich. +Jones, J. F., Jeanerette, La. Kiefer, Louis W., 901 N. Elm St., Henderson, Ky. Lake, Prof. E. R., Asst. Pomologist, Dept. of Agric., Washington, D.C. Littlepage, T. P., Union Trust Building, Washington, D.C. Lovett, Mrs. Joseph L., Emilie, Bucks Co., Pa. McCoy, R. L., Ohio Valley Forest Nursery, Lake, Spencer Co., Ind. Malcomson, A. B., 132 Nassau St., New York City. Mayo, E. S., Rochester, N.Y. Representing Glen Brothers. Meehan, S. Mendelson, Germantown, Phila., Pa. Representing Thomas Meehan and Sons. Miller, Mrs. E. B., Enid, Oklahoma, R. 7, Box 47-1/2. Miller, Mrs. Seaman, c/o Mr. Seaman Miller, 2 Rector St., N.Y. City. Morris, Dr. Robert T., 616 Madison Ave., New York City. Moses, Theodore W., Harvard Club, 27 W. 44th St., New York City. Pierson, Miss A. Elizabeth, Cromwell, Conn. Plump, Chas. H., West Redding, Conn. Pomeroy, A. C., Lockport, N.Y. Potter, Hon. W. O., Marion, Ill. Reed, C. A., Div. of Pomology, U.S. Dept. of Agric., Washington, D.C. Riehl. E. A., Alton, Ill. Roper, Wm. N., Arrowfield Nursery Co., Petersburg, Va. Rose, Wm. J., 413 Market St., Harrisburg, Pa. Rush. J. G., West Willow, Pa. Sensenig, Wayne. Schempp, G. C., Jr., Route 3, Albany, Ga. Shoemaker, Seth W., Agric. Ed. Int. Corresp. Schools, Scranton, Pa. Smith, Goldwin, Highland Creek, Ontario, Canada. Smith, Percival P., 108 S. La Salle St., Chicago, Ill. Tuckerman, Bayard, 118 E. 37th St., New York City. Van Duzee, Col. C. A., St. Paul, Minn. Walter, Dr. Harry, The Chalfonte, Atlantic City, N. J. Wentink, Frank, 75 Grove St., Passaic, N. J. Williams, Dr. Charles Mallory, 48 E. 49th St., New York City. Williams, Harrison, Erie R. R. Co., 50 Church St., New York City. +Wissmann, Mrs. P. deR., 707 Fifth Ave., New York City. Womack, B. F., Ancon Canal Zone, Panama.
*Honorary member. +Life member.
CONSTITUTION AND RULES OF THE NORTHERN NUT GROWERS ASSOCIATION.
Name. The society shall be known as the NORTHERN NUT GROWERS ASSOCIATION.
Object. The promotion of interest in nut-producing plants, their products and their culture.
Membership. Membership in the society shall be open to all persons who desire to further nut culture, without reference to place of residence or nationality, subject to the approval of the committee on membership.
Officers. There shall be a president, a vice-president, and a secretary-treasurer; an executive committee of five persons, of which the president, vice-president and secretary shall be members; and a state vice-president from each state represented in the membership of the association.
Election of Officers. A committee of five members shall be elected at the annual meeting for the purpose of nominating officers for the subsequent year.
Meetings. The place and time of the annual meeting shall be selected by the membership in session or, in the event of no selection being made at this time, the executive committee shall choose the place and time for the holding of the annual convention. Such other meetings as may seem desirable may be called by the president and executive committee.
Fees. The fees shall be of two kinds, annual and life. The former shall be two dollars, the latter twenty dollars.
Discipline. The committee on membership may make recommendations to the association as to the discipline or expulsion of any member.
Committees. The association shall appoint standing committees of three members each to consider and report on the following topics at each annual meeting: first, on promising seedlings; second, on nomenclature; third, on hybrids; fourth, on membership; fifth, on press and publication.
The Northern Nut Growers Association
SECOND ANNUAL MEETING
THURSDAY, DECEMBER 14, 1911, 10 A. M.
ROOM 191, NEW YORK STATE COLLEGE OF AGRICULTURE, ITHACA, NEW YORK.
President Morris: The meeting is called to order and I will first ask Professor Craig to make a few remarks on behalf of the College Director and the President of the University.
Professor Craig: It is my privilege and pleasure to welcome the representatives of the Northern Nut Growers' Association in this, their second annual meeting, to the New York State College of Agriculture. I regret exceedingly that Director Bailey, who has been avoiding out of state engagements this winter quite generally, made one about two months ago for this day, about a thousand miles away, which makes it absolutely impossible for him to be with us. He regretted this very much, and asked me particularly to impress upon you the idea that he was most anxious that this Association should meet here, and that all the facilities of the College of Agriculture should be placed at your disposal, for the purpose of making your meeting as profitable and as pleasant as possible.
President Schurman, whose time at this period of the year is much monopolized and who is by previous engagements occupied very completely this morning, has asked me to say to you that he hoped to be able to come over and join us informally some time during the afternoon. I wish then to impress the thought that, although the official representatives of the University and College are not with us, they have not forgotten this meeting. As a member of the Executive Committee, in charge of the sessions, I have made up a tentative program for this morning for the purpose of starting the meeting off; and as the President will undoubtedly tell you later on, this program is subject to revision and change according to the convenience of the members. It is proposed to occupy this morning with regular program subjects, and it has been suggested that this afternoon we take a couple of hours' leisure which we may use in examining the exhibits or in viewing the University, if you care to consider that an exhibit worth while. It will be our pleasure to furnish guides for those who desire to make an excursion around and through the University buildings.
Let me say in conclusion that I hope you will make use of the opportunities and facilities that are at your full disposal. The Department of Horticulture is located on the second floor. I would like you to make that office your headquarters, and make use of our clerical force, and such facilities as are available, to the fullest measure possible, so that your visit will be pleasant, as I am sure it will be profitable.
President Morris: The next order of business will be the report from the Secretary-Treasurer, and the report of the last meeting.
* * * * *
Doctor Deming: A meeting for organization of Northern Nut Growers was held, on the invitation of Dr. N. L. Britton, at the Botanical Museum in Bronx Park, New York City, on Nov. 17th, 1910.
Dr. Britton called the meeting to order, stated its purpose and presented specimens.
Those present were:
Dr. N. L. Britton, Director N. Y. Botanic Gardens. Dr. Robert T. Morris, 616 Madison Ave., New York City. Prof. John Craig, of Cornell University. Mr. T. P. Littlepage, Union Trust Building, Washington, D. C. Mr. A. B. Malcomson, Orange, N. J. Mr. Henry Hales, Ridgewood, N. J. Mrs. Joseph L. Lovett, Emilie, Bucks County, Pa. Mrs. Yardly (with Mrs. Lovett). Dr. Geo. Knapp, (at the request of Simpson Bros., Vincennes, Ind.) 21 Claremont Ave., New York City. Mr. C. A. Schwartze, 92 Stagg St., Brooklyn, N. Y. Mr. Nash, of the Botanical Museum. Dr. W. C. Deming, Westchester, New York City.
On the retirement of Dr. Britton Dr. Deming acted as temporary chairman and read a number of letters from persons interested in nut culture encouraging the formation of an association.
The chairman appointed Prof. Craig, Dr. Morris and Mr. Littlepage a committee to draw up a tentative constitution or set of working rules until permanent organization could be effected. The committee made the following report which was adopted with the understanding that the executive committee should consider the question of constitution and by-laws and report at the next regular meeting.
* * * * *
Name. The society shall be known as the NORTHERN NUT GROWERS ASSOCIATION.
Object. The promotion of interest in nut-producing plants, their products and their culture.
Membership. Membership in the society shall be open to all persons who desire to further nut culture, without reference to place of residence or nationality.
Officers. There shall be a president, a vice-president, a secretary-treasurer and an executive committee of five persons, of which latter the president and secretary shall be members.
Meetings. The association shall hold an annual meeting on or about Nov. 15 and such other special meetings as may seem desirable, these to be called by the president and executive committee.
Fees. The fees shall be of two kinds, annual and life. The former shall be $2.00, the latter $20.00.
In addition to the large number of letters showing a wide spread interest in nut growing, communications of especial interest were received from Prof. W. N. Hutt, State Horticulturist of North Carolina, Mr. W. N. Roper, former editor of the American Fruit and Nut Journal, and from Mr. Henry Hicks of Westbury, Long Island.
The election of officers resulted as follows:
President—Dr. Robert T. Morris, New York City.
Vice-President—Mr. T. P. Littlepage, Washington, D. C.
Secretary-Treasurer—Dr. W. C. Deming, Westchester, New York City.
Executive Committee: Prof. John Craig, Cornell University; Henry Hales, Ridgewood, N. J.; Prof. C. P. Close, College Park, Md.
Exhibits of nuts, nut literature, trees, grafting methods, a budding tool, etc., were received and shown from nineteen different contributors. A detailed account of these has been published and is on file.
The following resolution, introduced by Mr. T. P. Littlepage, was unanimously adopted:
Resolved, that the Northern Nut Growers' Association express its appreciation of the attitude of the National Nut Growers' Association in encouraging the organization of associations which have for their purpose the development of the nut industry, and we hereby pledge our support to, and our cooperation with, said National Nut Growers' Association. And be it further
Resolved, that we hereby acknowledge our great obligation to the many pioneer nut growers of the South who have done so much to put nut culture on a scientific basis, and that we express to them our deep gratitude for the fund of valuable information and data which they have worked out and made available.
The meeting then adjourned.
The Secretary-Treasurer has received for membership fees $108.00, and expended for postage, printing and stationery, telephone and telegrams, $59.27. Remaining in treasury, $48.73.
The following leaflets were issued during the year:
A reprint of Dr. Morris's article "Nut Culture for Physicians."
A list of societies, books and other publications devoted to nut culture.
A list of some of the chief nurserymen carrying nut trees in stock.
The President also published in the Garden Magazine for May an article on nut culture, in which he referred to our organization, as a result of which some 45 letters of inquiry were received by the secretary, covering the country from Canada to Texas and from British Columbia to Panama.
The leaflets, and notices of the annual meeting, have been sent to about 321 addresses, including the members, agricultural journals, nurserymen and nut dealers, government and state officials, state horticulturists, correspondents and persons who it was thought might be interested.
The following letter was sent to 21 leading nurserymen:
"The President of our association, Dr. Robert T. Morris of New York, asks me to suggest to you that it might be well for your firm, or some member of it, to join the association, to be present at the meetings and to take up the matter of raising such nursery stock as is in constant and growing demand by the members. We need to be in touch with those who are growing things commercially and if they are present at the meetings they will know what we want. The national association is largely made up of professional nurserymen."
Nov. 15, 1911.
Two nurserymen have accepted the invitation. Evidently the others do not yet think the northern nut grower one whose acquaintance is worth cultivating. We hope to convince them to the contrary.
The following letter has been sent to the state horticulturists of the northern states and the provinces of Canada.
"The Northern Nut Growers' Association desires your interest, your aid and advice, your membership and, if possible, your attendance at the meetings.
It would also be of help to the association in its work if you would give it information of those persons in your state who are interested in nut culture."
Nov. 15, 1911.
Cordial replies have been received from M. B. Cummings, Secretary of the Vermont Horticultural Society; from Le Roy Cady, Chief of the Division of Horticulture, Minnesota Agricultural Experiment Station; and from J. H. Poster, Professor of Forestry, New Hampshire Agricultural College.
Fifty postal card reminders of this meeting were sent to members and others a week ago.
The secretary has also made investigation by correspondence on the hickory bark beetle and the identity of Juglans mandshurica.
The response from all communications to the various officials of the Department of Agriculture at Washington has been prompt, cordial, interesting and helpful. This should certainly be very encouraging, if encouragement is needed, coming from men likely to be far-seeing as to the needs for, and the possibilities of, nut culture. Prof. Frederick V. Coville is conducting experiments in rooting hickory cuttings sent by the secretary. Prof. Walter Swingle offers his cooperation in experiments in propagation.
The general correspondence received by the secretary shows an interest and an enthusiasm that reveals the growing appreciation of the importance of the purposes for which this association stands.
(The following figures are brought up to date of going to press.)
Eighteen of our 60 members are from New York, 8 from Connecticut, 6 from Pennsylvania, 4 from New Jersey and Illinois, 3 from the District of Columbia, 2 each from Indiana, Virginia and Minnesota, and one each from Massachusetts, Ohio, Georgia, Louisiana, Florida, Colorado, Kentucky, Michigan, Oklahoma, Panama and Canada. Thus seventeen states, the District of Columbia, Panama and Canada are represented in our membership.
Eight of our members are women, one of them a life member, nine are professional nurserymen, eight are physicians, six are connected with educational institutions, three are lawyers, five agriculturists, two at least are capitalists, and all expect to be, two are in literature and there are one each of the following: clergyman, painter, insurance, secretary, railroads, senator.
The national association has 273 members of whom 52 are from the northern states. We ought to have all of these.
The secretary is keeping a record of the scattered articles, communications to agricultural journals and other literature relating to nut growing. He would consider it a favor if the members would send him information of anything of this kind that may come to their knowledge.
Mr. Littlepage: I move that the report of the Secretary-Treasurer be approved.
Professor Craig: I second that motion. I would like to add just a word, to the effect that it seems to me that the Secretary has started out in a very promising manner. He has not merely performed the routine duties of the secretary, but he has studied the case, and has presented in an analytical and striking form a good many facts not apparent on the surface, had he only given us the stereotyped matter in the conventional way; and it seems to me that this augurs well for the future of the Secretary's office. I trust he can keep up the gait. (Carried.)
Professor Craig: May I say that it seems to me there are one or two matters arising out of the Secretary's report which are worthy of special action? One is the question of the invasion of the Scolytus beetle; the other is the nomenclature of Juglans mandshurica. It occurs to me that it might be well to appoint committees on these subjects to report during the sessions of the society. I might say on the Scolytus matter, that I have conferred with Professor Comstock, who has been kind enough to say he would place the matter in the hands of one of his assistants, who will present to the society the latest we have on that subject; and in the event of a committee being appointed, I would suggest that that person, Professor Herrick, be made the chairman of that committee.
President Morris: I will appoint Professor Herrick and Professor Craig on the scolytus committee, and on the nomenclature committee I will appoint Doctor Deming and Mr. Barron.
In this connection, I will have to say, however, that I neglected to bring my correspondence relating to the nomenclature of Juglans mandshurica. I can say a word that the committee may wish to use. For a long while, I have been trying to trace the origin of the name Juglans mandshurica. It is applied to two different nuts. The one described in the United States government bulletin is the nut originally described by Maxim as Juglans mandshurica more than thirty years ago. That nomenclature has priority for two reasons: first, because of the date, and in the second place, because of the recognized standing of Maxim as a botanist. The Yokohama Nursery Company has been sending out a very different nut which they call Juglans mandshurica, evidently of the race of Juglans regia. The Juglans mandshurica of the government bulletin is like the butternut, the Juglans mandshurica of the nursery companies is evidently a race of Juglans regia. I have conferred with Doctor Britton, Sargent, and other authorities, and we have never been able to trace the name given to this walnut of the Juglans regia type, Juglans mandshurica, until by accident I happened to get word from the Yokohama Nursery Company to the effect that they had made up that name in the office a few years ago, not knowing that a previous Juglans mandshurica existed and had been named by Maxim. So that traces the rodent to its hole. The name Juglans mandshurica by Maxim is the proper name for the worthless butternut-like nut from China. De Candolle named the valuable walnut that has been sent out by the Yokohama Nursery Company Juglans regia sinensis. So both of these nuts have been previously named, and by authority.
Professor Craig: It is a question, then, of priority.
President Morris: Yes, a question of priority; but really the Yokohama Company had no right to make up that name. It was simply made up in the office as a matter of trade convenience, and they attached to this Juglans regia nut a name that had been applied to an entirely different nut, not knowing that this name had been previously applied. So there is a Juglans mandshurica and a Juglans regia sinensis, respectively.
Mr. Littlepage: Is the walnut, Juglans mandshurica, which you have been discussing, similar to the ordinary butternut of the Middle West, the Indiana white walnut?
President Morris: You can find nuts much alike on first inspection, but the mandshurica nut has six ridges in addition to the suture ridges. The leaf of Juglans mandshurica is sometimes a yard in length, with twenty-seven to thirty-one leaflets, sometimes—an enormous tropical leaf. The nut is usually too small to be valuable.
Mr. Littlepage: I have seen the butternut of the Middle West nearly similar, but it grows on the ordinary tree with white bark, and has small leaves.
President Morris: The general outline of the nut is about the same in both, but the air chambers are very much larger in the mandshurica than they are in the butternut and there is a marked difference in the flavor. You can distinguish them readily enough.
Mr. Littlepage: The butternut grows wild throughout the Middle West, usually along small water courses and alluvial lands. There are perhaps one hundred and fifty on a creek corner on one of my farms.
President Morris: They are very plenty here at Ithaca. In fact, you will find them in Maine and Nova Scotia.
Mr. Littlepage: I saw them in Michigan.
President Morris: I will state, that from two until four the members will view the collections, and make the tour of the Campus buildings. During that time the report on competition, or at least examination of specimens in competition, should be made, and I would like to appoint Professor Reed and Mr. Littlepage on that committee, and I will serve as ex-officio member of the committee. The other committees I can make up a little later. The next order of business will be the President's address. Mr. Littlepage, will you take the chair?
THE HICKORIES.
ROBERT T. MORRIS, M. D.
So far as we know, the hickories, belonging to the Juglandaceae, are indigenous to the North American continent only. Representatives of the group occur naturally from southern Canada to the central latitude of Mexico, in a curved band upon the map, which would be bounded upon the east by the Atlantic Ocean and the Gulf of Mexico, and on the west roughly by the Missouri River, until that river bends east from the eastern boundary of Kansas. From the angle of that bend the hickory runs approximately southwest into Mexico.
The exact number of species has not been determined as yet, because of the open question of specific or varietal differences in some members of the family. Sargent's classification at present includes eleven species: Hicoria pecan, H. Texana, H. minima, H. myristicaeformis, H. aquatica, H. ovata, H. Carolinae-septentrionalis, H. laciniosa, H. alba. H. glabra, and H. villosa. To this list may be added H. Mexicana (Palmer), which so far seems to have been found only in the high mountains of Alvarez, near San Louis Potosi in Mexico; and H. Buckleyi from Texas, which was described once by Durand, and since that time overlooked by writers, excepting by Mrs. M. J. Young in 1873, who included the species in her "Lessons in Botany." Professor Sargent tells me that the Buckley hickory will be included in the next edition of Sargent's "Manual of the Trees of North America." This brings the number of species up to thirteen. In addition we have well marked varieties: H. glabra odorata, H. glabra pallida, and H. glabra microcarpa, making sixteen well defined hickories that have been described.
Nuts of all of these hickories are in the collection of "Edible Nuts of the World" at Cornell University, with the exception of nuts of the varieties H. glabra odorata and H. glabra pallida.
In addition to the sixteen described varieties and species of hickories in America, we have an endless variety of hybrid forms, because cross-pollenization seems to take place readily between hickories of synchronous flowering time.
Five of the hickories: H. pecan, H. Texana, H. minima, H. myristicaeformis, and H. aquatica belong to the open-bud group, while the rest belong to the scale-bud group. The winter buds of the open-bud group resemble the winter buds of the walnuts in a general way, and in artificial hybridization experiments I seem to note a close relationship between the open-bud hickories and the walnuts.
There is no more promising work for the horticulturist than crossing hickories with walnuts, and crossing hickories with each other. Five hundred years from now we shall probably find extensive orchards of such hybrids occupying thousands of acres of land which is now practically worthless. The hickories are to furnish a substantial part of the food supply of the world in the years to come. At the present time wild hickories held most highly in esteem are: H. pecan, H. ovata, H. Carolinae-septentrionalis, and H. laciniosa. Several other kinds have edible kernels, sometimes of excellent character, but not readily obtained except by boys and squirrels, whose time is not valuable. In this group we have H. alba, H. glabra, H. villosa, H. glabra pallida, H. glabra odorata, H. glabra microcarpa, H. Mexicana, H. Buckleyi, and H. myristicaeformis. In another group of hickories with temptingly thin shells and plump kernels, we have a bitter or astringent pellicle of the kernel. This group contains H. Texana, H. minima, and H. aquatica. Sometimes in the bitter group we find individual trees with edible nuts, and it is not unlikely that some of them represent hybrids in which the bitter and astringent qualities have been recessive.
Among the desirable species of wild hickories there is much variation in character, and selection of trees for propagation is in its infancy. One reason for this has been the difficulty of transplanting hickories. Another reason is the fact that hickories do not come true to parent type from seed. A third reason is the length of time required for seedling hickories to come into bearing.
Concerning the first reason, the enormous taproot of young hickories requires so much pabulum for maintenance that when the trees are transplanted, with destruction of root-hairs along with the feeding roots, transplanted stocks may remain a year or two years in the ground before they are ready to send out buds from the top. On this account, the Stringfellow method has in my locality proven of value. This consists in extreme cutting back of root and top, leaving little more than a short club for transplantation. The short club does not require much pabulum for maintenance, and new feeding roots with their root-hairs get the club under way quickly, because there is little useless load for them to carry. The Stringfellow method further includes the idea that stock should be planted in very hard ground, and seems to be practicable with the hickories. The root-hairs which take up nourishment from the soil find it difficult to carry on osmosis in loose soil. The close contact obtained by forcing a way through compact soil facilitates feeding. On this account, autumn is perhaps a better time for transplantation of hickories, in the northern latitudes, at least. Callus forms over the ends of cut roots at all times when the ground is not frozen, and the more complete the callus formation the more readily are feeding roots sent out.
One of the main obstacles to propagation of hickories has depended upon the fact that nuts did not come true to parent type from seed. This is overcome by budding or grafting, and we can now multiply the progeny from any one desirable plant indefinitely. In the South grafting is nearly as successful as budding, but in the North budding seems to be the better method for propagation. The chief difficulty in grafting or budding the hickories is due to slow formation of callus and of granulation processes which carry on repair of wounds.
The propagation of trees from a desirable individual plant can be accomplished also by transplanting roots. A hickory root dug from the ground, divested of small rootlets, cut into segments a foot or more in length, and set perpendicularly in sand with half an inch protruding, will throw out shoots from adventitious buds. In my experimental work with hickory roots, in covered jars, surrounded by wet moss, but with the entire root reached by light, adventitious buds have started along the entire length of the root, and we may find this an economical way for root propagation, dividing up sprouting roots into small segments. The chief objection to this method of propagation as compared with budding is the length of time required for seedling trees to come into bearing, propagation from roots probably requiring the same length of time as propagation from seed, whereas by budding or grafting the bearing period begins very much earlier. Forty-six years ago Mr. J. W. Kerr of Denton, Maryland, planted three pecks of large shagbark hickory nuts, but of the progeny only about twenty were satisfactory, most of the trees bearing inferior nuts. These trees required from thirteen to eighteen years to come into bearing, and young trees that Mr. Kerr purchased from nurseries and planted were twenty-five years old before they began to bear. Others who have planted shagbark hickories and pecans state that nearly twenty years are required for the trees to come into bearing on an average. When budded or grafted the pecan sometimes comes into bearing in two years, and frequently in four years. We may anticipate that other hickories will act analogously.
The hickories prefer rich, well drained soil for best development of nuts, and an abundance of moisture, provided the land is well drained. Many of the hickories, however, are so adaptable to various soils that they often thrive in lands that are sandy, and dry, and almost barren. In the latter case, they have to maintain an enormous root system for feeding purposes, and this is detrimental to good bearing qualities. The mocker-nut, pignut, and hairy hickory, perhaps adapt themselves best to sandy soils. This feature may make them valuable species for planting when one has no other soil, because the stocks can be used for grafting better kinds.
While the hickories prefer neutral or alkaline soil, most of them will grow fairly well even in acid glacial tills. Their preference, however, for neutral or alkaline soils would suggest the use of a good deal of lime in acid soils, when hickories are to be grown in orchard form.
All of the trees in the hickory group are intolerant of shade and of competition with other trees. The more sunlight they can have the better. Most of us are familiar with the hickory tree standing alone in the cultivated field, which bears a heavy annual crop, when the neighbors at the edge of the forest bear sparingly. Hickories in forest growth put their energies into the formation of wood chiefly, and in the struggle for food and light devote very little energy to fruiting.
The best method for cultivation of hickories has been worked out only with the pecan up to the present time. With this species, it has been determined that clean cultivation with plenty of fertilization gives best results, as with apples. It is probable that Stringfellow's sod culture method will come next in order, and will perhaps be most generally used by nut orchardists, because it is less expensive and requires less labor. The sod culture method includes the idea of cutting all grass and weeds beneath the trees, in order to take away competition, allowing these vegetable substances to decompose beneath the trees and furnish food. There is no objection to adding artificial fertilizer, or a still greater amount of vegetable matter.
The enemies of the hickories are not many in the forest, where the balance of nature is maintained, but when man disturbs the balance of nature by planting hickories in large numbers in orchard form certain enemies increase, and must be met by our resources. Fungous and bacterial enemies are beginning to menace some varieties of the pecan in the South, and both in the North and in the South certain insect enemies are becoming important in relation to all valuable hickories.
The bark boring beetle (Scolytus) has been reported as destructive to hickories in some sections, the trees dying as a result of depredations of the larvae of this beetle.
I find a large borer at work on some of my hickories, but have not as yet determined its species. It may be the painted hickory borer (Cylene), or the locust borer. It makes a hole as large as a small lead pencil, directly into the trunk or limbs, and excavates long tunnels into the heart wood. The painted hickory borer is supposed to occur chiefly on dead and dying hickories, but the borer of which I speak is found in the vigorous young hickories in the vicinity of my locusts, which are riddled with locust borers.
In some localities involucre borers make tunnels between the nut and the involucre, interfering with the development of the kernel.
The hickory twig girdler (Oncideres) is abundant in some localities, but not as yet very destructive.
Hickory nut weevils destroy many nuts in some localities, and their colonies increase about individual trees markedly. In such cases, it is important to collect the entire crop each year from a given tree, taking pains to destroy all nuts which contain weevil larvae. These may be selected in a general way by dumping the freshly gathered nuts into a tub of water. Nuts containing weevil larvae will float for the most part, and in order to make sure of the destruction of larvae in the remaining nuts they may be placed in a closed receptacle, and carbon bisulphide poured over them.
One of the bud worms is sometimes very destructive to individual hickory trees which have developed colonies, the larvae destroying the axillary buds, and burrowing into the base of the petioles of leaves.
A new enemy which I found this year for the first time is the Conotrachelus juglandis. This beetle ordinarily lays its eggs in the involucre of the butternut. With the introduction of exotic walnuts, the beetle has changed its habits, and lays its eggs in the herbaceous shoots of walnuts and hickories. The larvae tunnel into the center of a shoot, and destroy it, or seriously interfere with its nutrition.
Among the enemies of the hickory we must not forget the common field mouse, and the pine mouse, which burrow beneath the surface of the ground, and in winter feed freely upon the bark of the roots of the hickories. They have destroyed many thousands of young hickories of various kinds in my nursery, and in digging up roots of old hickories for experimental root grafting I find that mice have been living freely for years upon the bark of some roots.
RANDOM NOTES
Aside from the facts which have been grouped together in this paper, certain notes may be of interest, as introducing questions for speculation.
Are we likely to find more species among the hickories than the ones already described? If so well described a species as the H. Buckleyi has almost escaped observation, and if H. Mexicana is confined, as it seems to be, to a very limited area, and if most of the hickories grow in regions where few botanists are at work, it seems to me probable that several species remain as yet undiscovered. These are likely to be species which lack means of defence, and which are restricted to certain small areas. If we make a parallel with other observations of recent discoveries, one thinks, for instance, in Ichthyology of the Marston's trout, the Sunapee sabling, Ausable greyling, and the Kern River trout, confined almost to a certain stream or lake, and remaining undiscovered for years by naturalists, although familiar to thousands of local fishermen.
Sometimes there is a very apparent reason for the check to distribution of a species. The men whom I employed to go into the mountains of Alvarez for the Mexican hickory tell me that the trees are so loaded down with mistletoe that they rarely bear a crop, and there are few nuts with well developed kernels to be found.
Distribution of a powerful species of hickory, like the pecan, seems to be limited in the North by incomplete development of the pistillate flowers. These are borne on the ends of the herbaceous shoots of the year, and the pecan has such a long growing season that in the North the pistillate buds, which are last developed, are exposed to winter killing. Southern limitation of hickories which have a very short growing period, like the shagbark, may be due to the fact that after a period of summer rest, new growth begins in the autumn rains, and this new growth may not lignify for winter rest.
By artificial selection we can extend the range of all hickories far beyond their indigenous range, which is limited by natural checks. Extension of range, adaptation to various soils, and changes in the character of the nut are likely to occur from grafting hickories upon different stocks of the family. Thus we can graft a shagbark, which does not thrive in poor sandy soil, upon the mocker-nut, which does grow in such soils. Some varieties of the species may grow freely far out of their natural range if they are simply transplanted. For instance, the Stuart pecan, which comes from the very shores of the Gulf of Mexico, is one of the hardiest pecans at the latitude of New York. I don't know about its northern fruiting as yet.
If the Satsuma orange grafted upon trifoliate orange stock gives a heavy, well flavored fruit, while the same variety grafted upon sweet orange stock gives a spongy fruit of little value, we may assume that similar changes in character of fruit will follow nut grafting. Perhaps the astringent feature of the pecan nut will be found to disappear when the pecan has been grafted upon certain other hickories. Sometimes undesirable results are obtained from such grafting; for instance, the pecan grafted upon water hickory stock has been found to grow freely for four or five years, and then to die back unaccountably.
Stocks of rapidly growing hickories, like the pecan and the bitternut, may serve to shorten the bearing time of slowly growing species, like the shagbark, when scions of the latter are grafted upon such stocks. At the present time I have shagbark grafted upon stocks of the pecan, shagbark, bitternut, mocker-nut, and pignut, but these are all young, and I cannot at the present time discern much difference in effect of stock upon scion.
In cross pollenization of hickories, I have not as yet discovered the best way to prevent the development of aphides and of other insects under the protection of the paper bags (which cover the pistillate flowers) sometimes to the point of destruction of flowers before nuts are started. It is probable that sprinkling the leaves with Persian insect powder, and leaving a little insect powder in the bag, will settle the question.
I have not as yet learned how to prevent squirrels from getting at hybridized nuts while they are still upon the tree. Squirrels cut through mosquito netting which is tied about nuts to prevent them from falling to the ground, and if wire gauze is used, they cut off the branch, allowing gauze and all to fall to the ground, and then manage to get the nut out of the gauze. The red squirrel particularly is a pest in this regard, and will even cut off the tape which is tied about the branches for marking purposes, for no apparent reason aside from pure mischievousness.
Nuts which are to be planted must be kept away not only from the squirrels, but from rats and mice. One of my farmhouses got the reputation of being haunted because of mysterious noises made by rats in rattling hybrid nuts worth a dollar apiece about between the partitions. The best way that I have found for keeping nuts for sprouting purposes is to have a number of large wire cages made. These are set in the ground, nuts are stratified in sand within these cages, and allowed to remain exposed to the elements during the winter.
It is probable that some of the hickories will be grown in forest form in future because of the increased value of the wood of the species. For growing hickories in forest form, it is probable that they should be set not more than six or eight feet apart at the outset. At ten years of age the first thinning will give a valuable lot of hoop poles. The second thinning will give turning stock. The third thinning will give wood for a large variety of purposes. I know of no tree which promises to return a revenue more quickly when planted in forest form than hickories like the shagbark and the shellbark, mocker-nut and pignut. These trees will not be expected to bear nuts, because in the struggle for food and light their energies will be directed toward making trunks.
Hickories are undoubtedly to be used for decorative purposes in parks and streets by future generations. The stately pecan, the sturdy shagbark, can be made to replace, South and North, the millions of useless poplars, willows, and other bunches of leaves, which please the eye but render no valuable annual or final returns. The chief reason why this has not been done is because people have not thought about it.
* * * * *
President Morris: This paper is not to be considered with the respect that is ordinarily due to a presidential address, but is open for discussion, and I would like to have any of my theories disproven.
Professor Craig: Doctor Morris has covered a very extensive field in his presidential address, and has raised so many interesting questions that I imagine the difficulty with you is to know just where to begin. Personally, and because I am not as thoroughly aware of the field of Doctor Morris' hybridization work as I ought to be, I should like to ask him what combinations of the hickories he has effected thus far. The field of hybridizing nuts is an exceedingly interesting one, and Doctor Morris has been the foremost worker in it. I am sure it would be interesting to you, as it is to myself, to know briefly what ground he has covered in the extensive range of his experiments.
President Morris: In answering that question, I am speaking from memory and may not speak correctly. I have made crosses back and forth between shagbark, bitternut, mocker-nut, pignut, and pecan. In the crosses I made, using pecans, pollen was received from the South and put upon the others. The number of crosses that are fertile I cannot state as yet, because I have not had experience enough in protecting these nuts, and many of the hybrid nuts were lost. Squirrels and mice destroyed the labor of three of my men and myself during one season. I have secured fertile hybrids between the pecan and the bitternut and between the pecan and the shagbark. If I remember correctly, those are the only fertile hybrids I have between hickories at the present time. In regard to crossing hickories and walnuts, I have crossed back and forth several of the walnuts, our black walnut, our butternut, the Siebold walnut, with the pecan, and with the bitternut, and have fertile hybrids. These are open bud hickories, and the open bud hickories seem to cross pollenize freely with the walnuts back and forth, while the scale bud hickories do not accept pollen readily from the walnuts. I would rather perhaps not make a report to this effect for publication at the present time, for two reasons. In the first place, I am speaking from memory; in the second place, rats, mice, squirrels, small boys, visitors, and high winds have made such inroads upon my specimens, and upon my work, that it is not quite time to report. I am merely speaking offhand in a general way, stating that the hickories, open bud and scale bud, both seem to cross rather freely back and forth. Open bud hickories and the walnuts seem to cross rather freely back and forth, while the walnuts and the scale bud hickories apparently do not cross so readily back and forth.
Professor Craig: In growing your hickories from root cuttings, have you had any trouble from excessive sprouting?
President Morris: Anywhere from one to eight sprouts will start from adventitious buds at the circle near the ground, and then I break all these off but one, letting that one grow.
Mr. Wilcox (Pennsylvania): How do you prepare your stocks for budding and grafting, in pots?
President Morris: I have tried practically every method that has ever been described, and the only successful method that I have now has been topworking vigorous sprouts of one year's growth. That is, I would cut off the tops of the trees now. Next spring those tops send out very vigorous sprouts. I bud those early in August or the latter part of July, or else in the following spring, sometimes, we graft them; and in grafting, it is quite important to cut longitudinally at one side of the stock, and go clear to the cambium layer. That gives the flexible slice on one side, and adapts itself to the tying.
Mr. Wilcox: Have you prepared any stocks in pots at all?
President Morris: Yes. I personally have to leave these to others. I tell my men to do it, but it is rather new work for them, and I give them so much to do that things are apt to be neglected; and just a moment of neglect at the wrong time will wipe out a whole year's work. I have not cared very much at the present time for root grafting in pots. I have lost a great proportion of the grafts, and it does not at the present time seem desirable; but I believe if that is done in hot houses with the ground warmed from the bottom, it is very apt to succeed. Give them plenty of time for granulating. They granulate very, very slowly.
Mr. Wilcox: What kind of pots do you use?
President Morris: Some Professor Sargent showed me, long, made for the purpose.
Mr. Collins (Pennsylvania): You spoke of the hairy hickory. What hickory is that?
President Morris: Hicoria villosa, that you find from Carolina southward.
Mr. Littlepage: You spoke of the Stuart as being the most hardy pecan in the latitude of New York. I presume you meant of the southern pecans?
President Morris: It seems to be one of the hardiest anyway. Even Virginia forms don't stand it through the winter as well as the Stuart. Mine are not fruiting as yet.
Mr. Littlepage: What varieties have you there?
President Morris: Appomattox and Mantura are northern ones I have.
Mr. Littlepage: Have you none of the Indiana varieties?
President Morris: Yes, I have the Indiana varieties on northern stocks, but those have only gone through one winter. They went through all right. I would say that the Stuart is quite as hardy as those.
Mr. Littlepage: I have observed the Stuart in Indiana. A friend of mine has a small orchard of several varieties of pecans. I notice some places where the Stuart has lived six or seven years, and then some particularly hard freeze has frozen it back. I have a letter from Mr. Jones in Louisiana, in which he says they had a recent freeze, and every variety of pecan he had there had suffered, except the Stuart. I don't recall whether he mentioned the Moneymaker in a previous letter or not, but he did mention the Russell and some other varieties.
President Morris: We have a number of pecan trees about New York that have been grown on private estates. Pecans have been planted in Connecticut and Massachusetts. You run across seedling trees here and there, and a good many of them are perfectly hardy. They are very apt to be infertile. The staminate flowers are apt to be destroyed because they mature so late, and they may not carry any nuts. Pollination is imperfect as a rule, and nuts may not fill.
Mr. Reed (Washington, D. C.): But trees of Stuart are in bearing?
President Morris: I don't know about bearing. Three years they have stood a temperature of twenty below zero, so that is a pretty good test.
Mr. Reed: You haven't seen any nuts yet?
President Morris: No, I haven't seen any nuts; but they mature their wood, and if they mature their wood, they are likely to mature staminate and pistillate flowers.
Mr. Littlepage: While it is true they may mature staminate and pistillate blossoms, the question arises whether or not the growing season is going to be long enough at the end to mature the nuts. I notice in going through wild groves in Indiana, once in a while you have a tree which never matures any nuts, though it has bountiful crops. The frost gets them.
Professor Craig: There is evidently a lack of summer heat to ripen fruit. Before we get quite away from this subject, I would like to ask Mr. Roper if he has noticed any striking differences in the hardiness of Stuart and other northern forms of the pecan in his particular locality. Does Stuart maintain its reputation for hardiness in his locality? We are interested in that question from the northern standpoint.
Mr. Roper (Virginia): I think it does, but that is discussed in a paper which I shall read some time here in the meeting. Both the Stuart and Moneymaker have done better with us than any other of the southern varieties when they are budded on hardy stocks. The grafted trees do not do well with us.
President Morris: Professor Lake, will you speak on any of these points?
Professor Lake: I am learning much and prefer to continue a learner. I shouldn't know anything about this crossing, except in the case of the Juglans regia and the oaks of California. That is one case that was not mentioned. We have a remarkable hybrid between the native oaks and the Persian walnut. It is remarkable in many ways. It has foliage that is perhaps half way between the oak and the walnut, and the nut on the surface looks like a small walnut, and on the inside it is between a walnut and an acorn. I had an opportunity to sample the flesh, but it is not edible yet. They are interested in the work very much, especially at Chico and the Southern California Station.
President Morris: It is said to be a cross between the live oak and the walnut. It seems absolutely impossible, but I have seen the nuts, and a photograph of the tree.
Mr. Reed: We haven't devoted a great deal of attention to the hybridization of nuts in our Department work. There is one thing that occurred to me, as I sat here, merely of passing interest. A gentleman in Mississippi sent a specimen of foliage, together with berries, from what he said was a hybrid between the pecan and the China berry; and he had the evidence, because the parent pecan tree stood right there, and the China berry was the other parent tree! He wanted world wide attention called to that. They were taken to the botanist, and he recognized them as one of the ordinary soap berries. There was a similar case this fall. A gentleman in Texas exhibited some nuts at the State Fair at Dallas that he said were a hybrid between the mocker-nut, the common hickory there in Texas, and the pecan. He said that the parent trees stood near one another and that the pecan blossomed some years about the same time that the hickory did, and in those years the hickory nut was long, and in other years it was short. Somebody sent one of the nuts to Mr. Taylor, Assistant Chief of the Bureau of Plant Industry. He sent the nut on to me, and I looked it up. I struck Texas on one of those cold wave days, and drove five miles out and back in a Texas livery rig, and found an ordinary hickory that bore nuts just a little different from others. That is one way the Department is called upon to ferret these things out.
Mr. Littlepage: I would like to ask Mr. Reed what information he has as to the success of pecans bearing when grafted or budded on other varieties of hickory? I say that because I know from traveling around through the country that there is a widespread impression that it is possible to have very extensive pecan orchards throughout the North by topworking the wild hickory. I have had some little experience along that line, but I don't know what the facts are; and Mr. Reed has made an extensive trip recently for the Department of Agriculture, collecting data in reference to the pecan.
Mr. Reed: The present situation, so far as we have been able to gather the information, is just this. The pecan has been grafted on a good many species of hickory, all the way from Virginia south to Florida, and west to Texas; but rarely ever can we find an instance in which they have produced satisfactorily after they have come to a bearing stage. We find that they unite readily ordinarily, and grow rapidly; but the pecan eventually proves to be a more rapid grower than the hickory, and when it catches up and is the same diameter, then the pecan growth is slower, and while they bear a little the first few years, later on they are not productive. I don't wish to say that is final, but it has been the experience so far. You will find most enthusiastic advocates of pecan on hickory where it hasn't been tried for any length of time. The men who try it find it unites readily and makes this quick growth, and think the question is solved. But aside from a few instances in Texas, I don't find very encouraging reports. It may be due largely to the fact that the right varieties of pecan haven't been used. We know that in the early history of pecan culture the Rome and Centennial and some others that are light bearers were used; and then the pecan on hickory has been looked at as so much saved, and they haven't been given much attention. It is still very much a matter of doubt, but is not in a very favorable light at present.
Professor Craig: I would like to ask Mr. Reed if he has looked over Mr. Ramsey's work recently at Austin, Texas.
Mr. Reed: I was at Mr. Ramsey's last year, and I don't recall that that matter came up at all.
Professor Craig: Didn't you see his plantation of top worked hickories?
Mr. Reed: I didn't know he had topworked hickories. He has topworked pecans. Professor Kyle of the Station in Texas has recently issued a bulletin on that very thing, and he cites a number of cases in which he concludes that there will be a favorable outcome; but for some reason, in the instances which he cites, the trees haven't borne very much. They attribute it this season in one instance to the fact that they had a storm at pollinating time, and last year some other accident happened that prevented them from maturing after a quantity of nuts had set.
Mr. Littlepage: I mention this at this time because I want to get Mr. Reed's testimony in the record, because I think that every prospective nut grower must go through this stage. A year ago I undertook on my farm in Indiana to bud the pecan into other varieties of hickory—I have a great many wild hickories growing all over my farm,—shagbark, shellbark, and different varieties of those even. So I went to work and budded perhaps one hundred of those trees, and for a while it seemed that there was going to be a great degree of success. I budded them all upon the limbs where the bark was thinner, and tied the bud in with waxed cloth very tightly; and by absorption the majority of the buds lived a week or ten days. After that, there was perhaps a third of them alive. For the next two weeks, we could find an occasional bud that remained green, and then the number became so very small that I gave up the idea that any would live. But this spring I found a few of these had started to grow, but I had tied them so very tightly that in some instances where there had been a growth of an inch or two, the bud part had been cut in two. Then I undertook it on a much smaller scale. I cut back eight or ten small hickory trees three to four inches in diameter, let them throw up water sprouts, and budded into these. The bud wood I used stuck very tight, and I examined the buds in November, and there were quite a number alive of the Greenriver and Huntington varieties of pecan. Whether they will grow finally remains to be seen.
(A discussion then occurred as to holding the afternoon session and it was decided to continue the business during the afternoon, instead of visiting the Campus.)
President Morris: I would like to comment on one point made by Mr. Littlepage. He has given us perhaps the reason why pecans die back when grafted upon other stocks. Mr. Reed, that is an extremely important point. He has shown that the pecan grows so much more rapidly than other hickories that when it has arrived at a proportion to be supported by the root of the other hickory, it then ceases bearing because all the energy is required for maintaining this new pecan top that tries to grow faster than the hickory, if that is my understanding of this point.
May we not graft freely back and forth hickories of kinds which have about the same rate of growth, and may we not graft other kinds of hickories upon pecan stock, for we don't care how much nourishment is given to a fine young shagbark?
Mr. Littlepage: That is a fine point.
President Morris: I am very glad Mr. Reed brought up that point. It is going to save thousands of dollars if it is a fact recognized in time, because many would go to putting pecans upon other hickories. We may learn that certain kinds of hickories can be grafted to advantage upon other stock, however.
Mr. Reed: There is another point right there I would like to have your views on, and that is, the smaller the hickory is at the time the pecan is grafted on it, the greater will be the influence of the pecan on the hickory.
President Morris: It can drag the stock along perhaps. It has been proved, I think, that a graft has a certain influence upon the stock, and in some cases can drag it along willy nilly to a certain extent. The root and the top get to balance each other fairly well if the root is very small at the time the graft is put on. Most of the trees that have been topworked to pecan have been various kinds of large hickories. Perhaps if you were to take a shagbark hickory one to two years of age and graft it, the pecan top would dominate or control that root, no matter whether it wanted to grow or not.
Mr. Reed: The claim is sometimes made that if the pecan is grafted on other hickory young enough, it will transform the hickory completely. It will make a sufficient root system to feed the pecan as well as the pecan root would. But I have never seen that demonstrated.
President Morris: That is speculative. It is a very valuable point, one of the sort of points that would naturally be brought out at a meeting of this kind.
Mr. Reed: Have you seen that with other fruits, Professor Craig?
Professor Craig: Yes. Each variety of apple produces its own kind of roots without reference to the seedling stock. That is to say the scion overrules the root in budding or grafting upon one or two year old seedlings.
President Morris: A parallel that comes to mind now is the grafting of Burbank's Royal walnut upon ordinary walnut stock. When that was done, his Royal walnut was said to drag the other walnut along.
Professor Craig: I think it is a very valuable suggestion. I am not sure I will go as far as the President has gone; but I think it is exceedingly suggestive, and worthy of careful consideration.
Mr. Rush (Pennsylvania): I find the same experience in some instances, that the graft outgrows the stocks. That is a peculiar instance of the work of improper unions. Eventually the stock pushes up and forms a perfect union in growth, with the Persian walnut. This is particularly applicable to pecan and hickory. I suppose Mr. Reed will bear me out in that, with regard to English walnut and black walnut.
Mr. Reed: Oh, yes.
President Morris: You occasionally see a variety of apple grafted on another in which the graft part gives the tree a sort of slipshod appearance. How about the bearing in that kind of a tree?
Professor Craig: They usually bear heavily where the food supply is restricted.
Mr. Reed: That would make our pecans bear more heavily on hickory stock than on their own.
Professor Craig: As a matter of theory, they ought to. The bearing ought to be increased, because it is a system of girdling, or brings about the same effect,—in other words it restricts the return flow of the elaborated food. The food is checked at the point of union. Another parallel is in the case of Prunus domestica, the European plum, when worked on Prunus Americana, the American plum. In that case, the top always outgrows the stock, and in ten years it presents a very curious appearance. It presents the appearance of a very top-heavy head on a very spindling stem. The bearing is usually encouraged, but the fruit is usually small. The amount of fruit measured by numbers is increased, but the amount of fruit measured by the size of individual specimens is decreased.
Mr. Collins: Isn't the size of the fruit increased in the case of apples?
Professor Craig: By topworking, usually, it is, but that doesn't contemplate such an extreme case as that. It means when the union is reasonably uniform, when there is a reasonable affinity between stock and scion. But in extreme cases we get the opposite result. Reproduction is encouraged, but size of fruit is checked.
President Morris: I would like to hear from Mr. Rush or Mr. Pomeroy in connection with the hickory.
Mr. Pomeroy: I haven't ever tried any experiments with the hickory.
President Morris: We will discuss further some of the points that have been suggested in this paper, because it seems to me we are along a good line of cleavage, and this line of cleavage may dispose of some questions that we haven't discussed. One question brought up was if the bitter, astringent qualities are likely to be recessive among hybrids in the trees which have bitter nuts.
Mr. Littlepage: I made a trip through Missouri and Arkansas a year ago, and while there, took occasion to go into the forests, and investigate to some extent the Arkansas and Missouri hickory and pecan. Among other things, I found two hybrids, one of the pecan and one of the pignut, one of which was bitter and inedible, the other a fairly good nut. I have both of them with me here today. One of them was very astringent and bitter, the other had taken more the quality of the pecan as to meat, and was a fairly good substitute. I don't know what the reason for it is, that one is fit to eat, and the other isn't, when they are both hybrids between the pignut and the pecan.
Doctor Deming: How did you know they were hybrids, by the appearance?
Mr. Littlepage: Yes, the appearance is unmistakable. The pignut characteristics are very prominent, also the pecan characteristics.
President Morris: Have the members anything to say about the Stringfellow method of transplanting hickories?
Doctor Deming: I have had very little experience in transplanting hickories, but I set out two Hales hickories I got from Meehan, and they are both living, although they have made little growth in some three years. Can you tell us what stocks the Hales hickory is grafted upon?
Mr. Brown (Pennsylvania): Upon the bitternut. All there are have been upon the bitternut from the start.
Doctor Deming: Mr. Littlepage, what do you think of the future of topworking our seedling hickories in the North with improved varieties of hickory or pecan,—the commercial future?
Mr. Littlepage: It is largely speculative. I suppose it is the province of every nut enthusiast to have an opinion about these things. In fact, I find it is encouraging to talk to the fellow who has an opinion. My notion is that there is a great future for topworking the various varieties of the hickory in the North to the desirable forms of the hickory, that is, of the hickory other than the Hicoria pecan. On my farm I expect next year to devote some time to topworking the various hickories I have to the desirable varieties of the shagbark. I think that can be done throughout the whole country. The shagbark seems to be indigenous to such extensive latitudes, that it seems to me there are great possibilities along that line. I observe that around here we find many of those trees. I have some very beautiful shagbarks that came from Canada. My opinion is that it will be successful. I think the reason the pecan has not proved very satisfactory upon the other species of hickory is that most of those hickories have a close grained wood, and that the distribution of available food depends largely upon the amount of sap. The Hicoria pecan is a much coarser grained wood. The flow of the sap upward is facilitated much more than the flow of the sap upward through the hickory stock of other varieties. I believe that is the reason the theoretical rule would probably not work in this case, simply because the distribution of sap cannot take place fast enough through the tight, close grained stock of other varieties of hickory. Otherwise, I don't see why the rule would not obtain, as with fruits. The experiences Mr. Reed gives, I think, are generally recognized by those who have experimented with them to any extent. I noticed in visiting Mr. Roper's nursery he had one very beautiful specimen of the pecan grafted on a hickory. That was the Stuart, was it not?
Mr. Roper: The Moneymaker. It had made a growth of four or five feet in two years.
Mr. Littlepage: Do you know the variety of hickory that it was topworked to?
Mr. Roper: Just our common hickory, I suppose the pignut.
Mr. Littlepage: It made beautiful growth from the wood standpoint.
Mr. Roper: Mr. Reed's point was that it would do that till it got by the period of good nutrition from the root. Professor Craig says the elaboration of food from the pecan top more than overcomes the deficiency.
Professor Lake: I would like to question Mr. Littlepage's physiological ground for the lack of proper fusion of liquids between the pecan and the other hickories. I believe it is not authenticated that the water supplies from the earth would not distil as fast in the close grained hickories as in the more open grained pecan. At least, the very close grained, firm woods of the tropics transmit a tremendous amount of water, much in excess of many of our fine grained woods of the North. And it seems to me I wouldn't like to have this Association go on record as vouching for this explanation exactly. It seems to me there are better explanations. Lack of fusion is not due to the amount of water that is carried up, but rather to the fact that the root system of the hickory does not develop fast enough to collect water to transmit.
Mr. Littlepage: I am very glad to hear Professor Lake's statements. My suggestions were given only as a possible theory that occurred to me, and I don't vouch for their accuracy. There must be some explanation to controvert the general rule which Professor Craig has given us.
Professor Craig: May I add one word? When a stock and scion unite, the union is really a mechanical one. It is a union of cells, and in that respect it is simply mechanical, not a physiological union. The different life types or character of the scion and top do not fuse, but we have a mechanical union of cells, and that mechanical union is as clearly shown forth as possible when we make a section through the point of union. If your type of cell in the stock differs very materially from the type of structure in the scion, the union is unsatisfactory. If the types of tissue are much alike, the union is good and you do not have either overgrowth of stock or undergrowth of scion very much, but you have what is called a good union. It is to some extent a question of mechanics, in my judgment, influenced by the cell structure of stock and scion. If you have a good, smooth union, the two grow equally. Where you have overgrowth of scion, you usually have a starved root, because the food which is to be returned elaborated is checked at the point of union, the root is starved, and you have a short lived tree, because your root system, which ought to receive its share of the distributed food, is underfed, finally weakens, and the whole structure fails.
Professor Lake: You may have mechanical union, but you can't have the after fusion in which you are going to have proper function of stock and scion.
Professor Craig: Each cell functions after its own kind. It is a question of passage or transmission of food through that carrier, after the union is effected. If the character of the two types differs very much, the transmission of food is checked and is difficult.
President Morris: There is another mechanical point I'd like to ask about. When the two types of cells differ, will the difference in degree of capillarity regulate the amount of pabulum distributed, or does it depend upon negative and positive pressure?
Professor Craig: That is a very difficult question, because it isn't settled at the present time what credit we should give to capillarity and what to root pressure in sap circulation.
Mr. Reed: There is another question I would like to ask Professor Craig. Supposing you have a mechanical union perfected, what is the difference in the food that different species of the same genus transmit? Has that been worked out?
Professor Craig: I don't think so. Of course, there is a difference in the food. That is proven, because there is a difference in the quality of the food. The tree machine, the tree factory speaking individually, evidently makes different products, and that is shown by the different quality of nuts. That is all we know about it.
Professor Lake: That part below the scion still continues to be normal hickory, and that part above, pecan, so really it is not a matter of distribution of water supply by gravity or other pressure, but rather a distribution of the proper amount of elaborated food; and that is transmitted through the cell itself, not the cell walls. Because this top makes a food that is different from the normal requirements, or because the latent character of those cells below does not respond to the food supply as actively as the part above, is the whole question, it seems to me. If the cells below functioned as the cells above, there would be no question about the stock and scion being the same.
Mr. Littlepage: Of course there must be sufficient flow of sap to distribute food. The hickory root might not send the flow of sap as fast as the pecan top would like.
Mr. Reed: Is Mr. Lake's point always true, that the stock below the point of union remains a normal hickory?
Professor Craig: I don't believe there are more than one or two exceptions noted to that, and those exceptions are recorded under graft hybrids.
Mr. Reed: A seedling pecan tree owned by Mr. B. M. Young of Morgan City, Louisiana, was top worked with scions from the McAllister hican some seven or eight feet above ground, and later on the bark of the pecan trunk below the point of union became scaly like that of the hican above.
Professor Lake: That would suggest something worth while, if that part below would produce fruit like the part above, but I would want to question a little the modification in bark characteristics being a direct result of cross grafting.
Mr. Reed: Of course, it was no check—only one instance.
Professor Craig: There are one or two others that are authentic. I have known a case of plum. Here we have the plum stock, we will say it is Prunus Americana, grafted with Prunus triflora, the Japanese, then later on, Prunus domestica is put on top. I have seen a sprout from triflora bearing Japanese plums, while the top of the tree bore Prunus domestica, although there was only a small section of stem in there between our two distinct species. They were perfectly normal.
President Morris: Each elaborates its own kind of food in its own kind of cell. I would like to hear from Mr. Brown and Mr. Wilcox on this matter of grafting—the influence of stock on scion.
Mr. Wilcox: We had a good show of stocks, but instead of allowing them to become established in the pots, we grafted them as they started into growth after rooting. Had they been established, we would have expected better results.
Professor Craig: What method do you employ?
Mr. Wilcox: Side grafting.
Professor Craig: Do you mean whip grafting?
Mr. Wilcox: Side whip grafting.
Doctor Deming: I would like to ask Doctor Morris what he thinks of the practical future of grafting our hickory seedlings with improved varieties of hickory or pecan, and the method most likely to succeed,—whether grafting or budding, and at what season. It is important to learn whether we can so graft or bud our hickory sprouts that within a few years we can hope to get something from them.
President Morris: We can only make a parallel with the pecan. If we know that it requires fifteen or twenty years for coming into bearing as a seedling tree, and if we know that it bears frequently in two, three, or four years after being grafted we can anticipate analogous action with other species of hickories. I haven't been able to get testimony from men who have grafted hickories. One man told me he thought shagbark grafted upon other shagbark, topworked, came into bearing in seven or eight years. Another man told me that his came into bearing in a much shorter time than it would otherwise, while with one particular variety, the Hale, I think that twelve years has been required for the tree to come into bearing.
Doctor Deming: I have a communication from Mr. Hales in which he speaks of a tree grafted in 1880, but doesn't say when it began to bear.
Mr. Littlepage: He told me it has taken some of them twenty years.
Doctor Deming: But the pecan on hickory has been known to bear the second season, that is, topworked. Can we expect such results in topworking our own hickories?
Mr. Littlepage: I think so.
Doctor Deming: Are we going to have success in topworking, and by what method?
President Morris: I believe in the South they can graft, but in the North we have got to do it by budding. My best results have been late July or early August. I believe herbaceous budding promises a good deal.
Mr. Rush: Were those buds then of the year previous?.
President Morris: Those were buds from the year of the scion, and herbaceous stock of the year.
Doctor Deming: Mr. Littlepage has had some success in budding hickory very early, haven't you?
Mr. Littlepage: I was just stating that I started in last year to bud. I think it would be possible to make a pecan orchard bear early by budding into these hickories, ten, fifteen, or twenty years old. This next year I am going to try hickory on hickory. I am going to try three processes. I am going to try bark grafting, and whip grafting in the body of the tree which has been cut off. Then, I have quite a number of hickories each four or five inches in diameter that I have sawed off and allowed to put up clusters of water sprouts, and I am going to whip graft some and put paper sacks over them, and see which is the best.
President Morris: I have found budding the best.
Mr. Reed: Doctor Morris referred to the analogy of the pecan grafted on pecan as coming into bearing in two years. Do you account for that in the fact of its being a graft, or the fact that the wood you selected came from a tree that had the characteristic of early bearing?
President Morris: No doubt that characteristic was transmitted, and further, no doubt the grafted stock was used from bearing wood. Those points are all of interest.
Mr. Reed: Does the mere operation of grafting or budding influence earliness of bearing?
President Morris: Yes, if I understand the question rightly. A tree that might not bear for fifteen years as a seedling may bear in three years grafted.
Mr. Rush: I have Persian walnuts that bore two fine nuts the second year. I have young trees, one about thirty inches, and I am sure it will be full of nuts next year, unless some providential misfortune should intervene.
Mr. Reed: At what age did the original trees begin to bear?
Mr. Rush: Those were buds shipped to me from California.
Mr. Littlepage: I am firmly convinced that there is something in the process of budding or grafting that stimulates the growth. For example, I have scions that were not over four to eight inches long grafted on one year seedling pecans which, at the end of this season's growth, were as much as thirty inches high. All along in the same row where seedling pecans were not grafted, there is none over eighteen inches high.
Mr. Reed: To have made exact comparison, you would have had to take buds from your seedling nursery trees, and graft on other trees. You are comparing these buds from one tree with seedlings of another.
Professor Lake: I would like to ask if you didn't bud or graft the best stocks in the row too?
Mr. Littlepage: We took the whole row, as we came to it, but that particular tree might have been on some particularly favorable stock. It is a matter of a good deal of interest to see why a seedling which wasn't budded at all didn't grow as high as a scion which was budded in summer, stratified all winter, then put into the ground in an unnatural position.
Professor Craig: It is the same principle, I think, which we discover in pruning. If we prune heavily during the dormant season, the effect is increased vegetative growth. If we wish to stimulate the growth of an old tree somewhat debilitated, we go to work and cut off a large portion of the top. We don't disturb the root. The effect is that with the same amount of pushing power from the root, we have a decreased area over which that energy is spread, and it results in apparently increased growth. I am not quite sure if we were to measure it up in a scientific way, we would actually find it was increased growth. There are fewer branches, but they have made greater length. In the case of grafting our pecans, we cut off our tops, set a two-bud scion in the root, and usually but one starts and receives all the vigor from the established root, instead of the vigor being distributed over several buds on the original seedling top. We have as a result of that concentration of vitality increased growth. I think that theoretical explanation will stand fairly well, because it seems to be directly in line with the effect of winter pruning.
Mr. Reed: I would like to ask Professor Craig to what extent he would select seed for nursery purposes? What influence would the characters of the parent tree from which the seed came have on the grafted tree?
Professor Craig: I don't believe that we can expect the characters of our stock to affect the scion to any extent. I think what the nurserymen should have in mind and keep in mind is a good, vigorous stock, and as many stocks as possible,—as he can get out of a pound of nuts. Otherwise, I don't think it cuts much figure. In that connection there is a principle which I have discovered by experience, namely, that if you are growing stocks it is wise to get your nuts as near your own locality as possible. My experience last year in planting five hundred pounds of northern grown nuts in a southern locality, and five hundred pounds of southern grown nuts in the same locality, gathered in that locality, is that I got fifty per cent more trees from my southern grown nuts than northern, and trees that were fully thirty per cent better.
Mr. Littlepage: Where were your northern grown nuts stratified?
Professor Craig: They were not stratified. They were planted as soon as they were received, and they were received within two weeks from the time they were taken from the trees.
Mr. Littlepage: I am inclined to believe that if your northern grown nuts had been stratified in the North, and undergone the customary freezing and thawing, then had been taken up in the spring, you wouldn't have seen that difference.
Professor Craig: I think that point is well taken.
President Morris: There is no doubt about that. In that same connection—I would choose nuts for seed purposes of a mean type, for the reason that nature is all the while establishing a mean. The big pecan is a freak. If you plant big or small nuts, you don't get big or small nuts in return. You get both big and little seeking a mean.
Mr. Roper: The large nut will give a better tree. We have tested that out.
President Morris: Does that work out logically in that way, is it a comparative matter all the time?
Mr. Roper: We haven't worked that out in the bearing, but in the nuts in the row, the small nuts did not produce as large trees as the large nuts. We never tested the mean nuts. We did select some of the very smallest we had, and planted one of the northern and one of the southern type. They came up, but the trees amounted to nothing.
President Morris: The idea I meant to convey was that both very small and very large nuts are freaks, and neither likely to give as good a tree as mean types. What would you anticipate, Professor Craig?
Professor Craig: I think that would resolve itself on a practical basis from the practical standpoint. I think the mean or average sized nut would give you the best results. There is no doubt, as Mr. Roper said, the very small nut would give you weak seedlings. On the other hand, you couldn't afford to use the very largest, so that a mean between large and small would be the natural thing to choose. But we should do nothing to discourage the planting of the finest specimens, with the possibility of getting something unusually good. That is certainly the work for every amateur.
Professor Lake: Does that statement, that you think it doesn't make much difference about the parent of the nuts for stock, apply to walnuts?
Professor Craig: I haven't had any experience in walnuts.
Mr. Littlepage: I would like to ask Mr. Roper if he knows of any examples where selection of fine varieties of seed has not resulted in getting a more productive variety of the plant which he was producing?
Mr. Roper: Only one, and that wasn't in a tree.
President Morris: In regard to coming true to type, I think records have been made of many thousands of pecans, and I don't know of any instance where the progeny resembled the parent closely.
Mr. Pomeroy: Maybe someone could explain one of my failures a few years ago in planting some Persian walnuts. I went to another tree in western New York, and got a peck or more. They were planted the same day, in the same ground, and all came up. Those I got from another tree resembled a hill of beans, and stayed that way for three years. Why wouldn't those grow? In soil three feet from those, there were trees growing. Those nuts never did make trees. The nuts were of good size.
Colonel Van Duzee: As a practical nurseryman, I wouldn't think of planting nuts from a tree that I didn't know individually. We have had very much better success with nursery stock where we have chosen as seed medium sized nuts from vigorous trees with which we were acquainted. In the case of Mr. Pomeroy, I don't think there is any question but that the history of his tree would account for the failure. In other words, his nursery stock was undoubtedly from the results of years of slow growth on the part of the original tree, or unfavorable conditions of some kind. I don't quite agree with Professor Craig on the question of the influence of stock, because I believe it is really a very important point.
President Morris: We are not here to agree upon anything.
Colonel Van Duzee: I can't speak from the scientific standpoint, but I am quite sure that in the nursery business I shouldn't care to overlook that influence.
President Morris: When men agree, it means we are on stale old ground which has been thrashed over.
THURSDAY AFTERNOON, DECEMBER 14, 1911.
President Morris: The meeting is called to order. The first paper this afternoon will be that by Mr. J. Franklin Collins of the United States Department of Agriculture, on the chestnut bark disease.
THE CHESTNUT BARK DISEASE.
J. FRANKLIN COLLINS, Washington, D. C.
I presume some of you know as much about certain features of this chestnut disease as I do myself; for I have only worked over certain sides of the whole question. I also presume that you are all acquainted with the fact that this disease, which is known as chestnut blight or the chestnut bark disease, is without doubt the most serious disease of any forest tree which we have had in this country at any time, that is, so far as its inroads at present appear to suggest.
I want to call your attention to certain general historical facts in connection with the disease, facts which are familiar to some of you, but unfamiliar possibly to others. The Forester of the Bronx Zoological Park, Dr. Merkel, discovered in the fall of 1904, or had his attention particularly called in 1904 to the fact, that a good many chestnut trees were dying in his vicinity, a number sufficient to have attracted especial attention. He looked at the matter carefully, and decided that there was a definite disease on these trees. He handed specimens over to Doctor Murrill of the New York Botanical Garden; who worked out the disease, and decided that it was a new fungus which was causing the trouble. He named it Diaporthe parasitica, the name under which it is generally known today, although there is some question as to whether that is the one which should be applied to it. This, you remember, was in 1904—in the fall.
The first publication which appeared on the disease was in 1906, as I recall it. The publication which then appeared was Doctor Murrill's upon his investigations. The disease has spread very rapidly since then, so that today we know the disease in a general area indicated by the red color on this map. The green area indicates in a general way the natural distribution of the common chestnut. Since 1904 investigations upon the geographical range of the disease have been carried on so far as to show that the disease is now known over approximately the area indicated in red on that map. The northern limits of the disease are perhaps in New York State. Further east, it is known as far north as northern Massachusetts, mainly in the western part, and it is also known in Boston. There have been two or three cases of the disease found in the Arnold Arboretum. On the west, we have two cases in West Virginia, and the most southern station which I know of is in Bedford County, Virginia. But those are isolated stations beyond the area which is indicated here. I shall have a little more to say in regard to the distribution.
Before speaking of that, I want to call your attention to a few points in regard to fungi in general, points of common knowledge to all who have studied fungi or mycology. A fungus is a kind of plant which does not, on account of the absence of the green coloring matter, manufacture its own food. It is a plant which has, in other words, no green foliage, and as it has no green foliage, it must obtain its organic or elaborated food from some other source. The fungi have very aptly been termed the tramps of the vegetable kingdom, that is, they live on food prepared by somebody else. They can take certain organic substances and change them apparently into other organic matter which can be used by the plant. In the case of this chestnut fungus, we have a fairly typical fungus in certain respects. We have a vegetative stage of the fungus which is nothing more or less than a lot of threadlike structures penetrating the bark of the chestnut, the inner bark or the middle bark, and there drawing the organic matter from the bark of the chestnut and appropriating it to its own use. Fungi, like practically all other plants, have two stages of existence, one the vegetative or growing stage, the other the reproductive stage. Sooner or later the fungus will produce the fruiting bodies, after it has obtained a sufficient amount of food to justify the formation of these more highly organized structures. In the case of the fruiting body of the chestnut fungus, we have very small, pinhead-like structures, which come out to the surface of the bark, the vegetative portion developing through the interior of the bark. On smooth bark we find that these fruiting pustules are apt to appear all over the surface. With bark that is sufficiently old to have ridges and crevices, we find these fruiting bodies only in the crevices.
These fruiting pustules which you will see on this bark are the structures which produce the reproductive bodies, these latter being known as the spores. There are two types of spores which are produced by this fungus. One is the type which is commonly spoken of as the summer spore, the other the type which is spoken of as the winter spore. The winter spore is known from the point of view of the mycologist as the perfect stage of the fungus, that is, it is the more characteristic of this particular fungus. If we should make a cross section of the bark, we should find that the vegetative stage is running through the middle bark, and commonly the inner bark, sometimes in one place only, sometimes in the other only, sometimes in both. This vegetative stage later sends up in various ways a mass of tissue which results in the formation of pustules. These appear on the surface, sometimes more or less regularly rounded, sometimes rather irregular. In the case of the summer spore stage, we have inside the pustules a mass of tissue which is formed into spores. The interior of the spore mass, or at least portions of it, is somewhat mucilaginous, so that when moisture is applied a swelling of the interior mass is produced at a certain stage and something has to break. As a result, we have a mucilaginous mass pressed out through the break in the shape of a twisted thread, much the same as if you take a collapsible tube of paste and pinch it.
Now, one of those summer spore threads may contain anywhere from one to five million spores. I have tried to estimate the number in a thread of this sort which was about an eighth of an inch long, and by taking a certain portion of that thread, mounting it in a drop of water, and then counting over a certain measured area under the microscope, I have estimated, by multiplying, that there were 2,400,000 spores in that one thread. So you can imagine how many of these spores may be produced by a single diseased area which has produced perhaps four or five hundred of those pustules, each pustule containing anywhere from one to twenty threads. Each one of those spores may develop a new diseased area, provided it is transported to a fresh break in the bark of a chestnut tree. Fortunately, only a very small fraction of one per cent ever reaches the proper place for growth.
This last is what I alluded to as the summer spore stage. There is a winter spore stage, or technically, the ascospore stage, which comes, as a rule, later in the development of the fungus. In this same pustule, later in the season, certain sacs are formed. These have long necks which extend to the top of the pustule. These sacs are sufficiently large to be seen with the naked eye. They are dark colored. Inside these, we have a lot of smaller transparent sacs or cases in each of which we get eight spores, sometimes in one row, sometimes in two rows. Each spore can propagate the fungus.
We have, then, two types of spores, either one of which can reproduce the fungus under suitable conditions. There is still another way by which the disease may be kept going. The vegetative stage can survive the winter and continue growing the following year.
I will say right here that I am planning to give you merely an outline of this disease, and have time afterwards for questions which I think in a meeting of this sort are one of the most productive sources of information.
In regard to the rapidity of spread of this disease, I will merely call your attention to two cases as illustrations, or to certain facts, rather. One is that the disease, so far as our attention has been directed to it, has developed over the area indicated on the map since the fall of 1904. Another case is one which has occurred in Rhode Island, where I have had a chance to watch its development a little more closely than in other places, that is, more constantly. In the fall of 1908, after I had made over thirty excursions around Rhode Island, I was unable to find a single trace of this disease, and no one else was able to find a single case of the disease in Rhode Island. In May, 1909, I happened to be about five miles west of the city of Providence, and I found two or three cases, all in one rather restricted spot. Later, it was discovered a little farther south, and soon, a little to the north, so that at the end of the season of 1909 we knew of about ten cases in Rhode Island. At the end of 1910, a season in which very few trips were made with the special object of surveying for the disease, we had more than doubled the number of infections found. That led to putting someone into the field in 1910 to make a survey of Rhode Island. A man was also put into the state of Massachusetts for the same purpose. Mr. Rankin, in cooperation with the United States Department of Agriculture, made a survey of New York State, which has resulted in this map. A man was put into Pennsylvania and one into Maryland for the same purpose. As a result of the survey in Rhode Island, where at the end of 1910 we knew of less than fifty cases at the outside, we now know of very nearly 4000 cases. It has been much the same story in Massachusetts. At the beginning of this year, there were four towns in which the disease was known; now there are seventy-one. At present in Connecticut, the disease is known in one hundred thirty-two towns of the one hundred sixty-eight in the state, and the southwestern part of Connecticut is very badly infected, just as badly as the adjoining portions of New York.[A] |
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