Chapter I: Part 1

Transcriber’s Notes:

Underscores “_” before and after a word or phrase indicate _italics_ in the original text. Small capitals have been converted to SOLID capitals. Illustrations have been moved so they do not break up paragraphs. Deprecated spellings have been preserved. Typographical and punctuation errors have been silently corrected.

Commonwealth of Pennsylvania

FINAL REPORT
OF THE
Pennsylvania Chestnut Tree
Blight Commission

JANUARY 1 TO DECEMBER 15, 1913

1112 Morris Building, 1421 Chestnut Street,
PHILADELPHIA, PA.

HARRISBURG, PA.:
WM. STANLEY RAY, STATE PRINTER
1914

Pennsylvania Chestnut Tree Blight Commission

MEMBERS OF COMMISSION

Winthrop Sargent, _Chairman_ Bryn Mawr
Harold Peirce, _Secretary_ Haverford
Samuel T. Bodine Villa Nova
George F. Craig Rosemont
Theodore N. Ely Bryn Mawr

EXECUTIVE STAFF

Mark Alfred Carleton, General Manager
Samuel B. Detwiler, General Superintendent
Oliver D. Schock, Assistant General Superintendent
Thomas E. Francis, Field Manager, Western District
Joseph R. Wilson, Field Manager, Eastern District
David T. McCampbell, Chief Clerk

Irvin C. Williams, (Pennsylvania State Forestry Department),
Collaborator

SCIENTIFIC AND OPERATIVE STAFF

Frederick D. Heald, Pathologist
A. G. Ruggles, Entomologist
J. P. Wentling, Forester in charge of Utilization
Paul J. Anderson, Field Pathologist
F. P. Gulliver, Geographer
Caroline Rumbold, Physiologist in charge of Tree Medication
Joseph Shrawder, Chemist
Roy G. Pierce, Tree Surgeon
Keller E. Rockey, Forester in charge of Demonstration Work

Contents

Page.
Advance spot blight infections; treatment of various plants, 76-79
Ants as carriers of blight spores; experiments with, 44
Bast miner; relation of insect to dissemination of blight, 45
Beattie, Prof. R. Kent; Bibliography of the chestnut bark
disease, 95-121
Bibliography of the chestnut bark disease, 95-121
Blight investigation and inspection of chestnut nurseries, 40
Blighted sprouts around stumps of trees cut at Hummelstown, 90
Burning over chestnut tree stumps; statement of results, 77
Carbon county, (Mahoning Valley), blight conditions, 64
Carleton, Mark A., General Manager, Pennsylvania Chestnut Tree
Blight Commission; Final report of, 27
Cicada sting wounds favorable for spread of chestnut bark
disease, 45
Chemical investigations in connection with blight, 47
Chestnut trees a valuable factor in Pennsylvania forest wealth, 10
Chestnut trees, rapid growth of, 10
Chestnut trees in Pennsylvania; threatened extermination of, 10
Chestnut cordwood, reduced freight rates on, 57
Chestnut nursery stock; regulations governing shipments of, 91
Chestnut orchards and nurseries, protection of against blight, 29
Chestnut bark disease; fake remedies for, 30
Chestnut trees, various diseases of, 42
Chestnut tree medication, results of, 48
Chestnut tree blight exhibits at museums and schools, 58
Chestnut timber; deterioration of blighted, 56
Chestnut tree blight; methods of dissemination, 63
Chestnut tree blight; combatting the fungus, 10
Chestnut trees; products of blighted trees marketable, 11
Chestnut tree blight; how destructive pest was spread, 11
Chestnut tree blight; discovery of its prevalence in China, 28
Chestnut Tree Blight Commission; active work suspended with
regret, 12
Chestnut tree blight infection in Western District, 37
Chestnut tree blight; first report of appearance in Pennsylvania
filed by Harold Peirce, of Haverford, Montgomery county, 17
Chestnut tree blight in Wildwood Park, Harrisburg; successful
treatment of, 30
Chestnut tree blight exhibits; where made, 32
Co-operative work of U. S. Department of Agriculture and
Pennsylvania State Forestry Department, 33
Creosoting peeled chestnut stumps; tabulated results of, 78
Cutting-out process; effectiveness of treatment of method, 27
Detwiler, Samuel B., Superintendent. Reports of observations
on sanitation cutting of blighted chestnut areas, 63
Discovery of chestnut bark disease in China, 28
Eastern Pennsylvania blight conditions, 67
Eradicating the chestnut blight; estimated cost of operations, 78
Field work of scouts and valuable results obtained, 36
Field work in Eastern District, report relating to, 38
Field laboratory work and special investigations, 43
Galls on chestnut and relation to blight infections, 47
Geographical work; report of observations, 52
Gulliver, Dr. F. P., Geographer; Report of geographic work, 52
Harmless saprophyte in Western Pennsylvania, 38
Heald, Dr. F. D., Pathologist; Investigations of tree diseases, 40
History of early efforts to eradicate blight in Pennsylvania, 17
Infection of chestnut in Western Pennsylvania; tabulated report, 37
Infection centres on advance line of the blight, 71
Infection at Orbisonia, Huntingdon county; tabular statement, 72
Insects; beneficial by destroying spores of blight, 28
Insects as carriers of the chestnut blight spores, 42
Insect investigations; valuable facts ascertained by, 44
Law, amendment to chestnut blight, 94
Legislative action to control blight in Pennsylvania recommended, 22
Lime-sulphur solution to prevent spread of blight, 51
Local field work; how conducted in generally infected districts, 40
Main Line Citizens’ Association; valuable services rendered by, 19
Message from the Governor suggesting legislative help, 21
Mickleborough, Dr. John W.; combatting the chestnut blight, 19
Murrill, Prof. W. A.; plan proposed to combat chestnut blight, 23
Nursery inspections; regulating shipment of nursery stock, 28
Nursery chestnut stock; list of inspections, 43
Official letter from the Commission to Governor Tener, 9
Official report of the Chestnut Tree Blight Commission, 9-13
Origin of the chestnut blight disease, 11
Oldest infections located near New York City, 9
Pennsylvania Chestnut Tree Blight Commission, Members of, 1
Pennsylvania Chestnut Tree Blight Commission; Executive Staff of, 1
Pennsylvania Chestnut Tree Blight Commission; Scientific and
operative staff, 1
Pennsylvania initial State to combat spread of blight, 10
Pierce, Roy G., Tree Surgeon; Report of tree surgery work, 50
Production of blight spores, 41
Publications relating to the chestnut blight, list of, 95
Publicity work; valuable assistance rendered by newspapers, 59
Publications issued by the Commission; reports and bulletins, 33
Pycnospores and ascospores; development and dissemination of, 42
Regulations for chestnut nursery inspections, 93
Reinspections for blight; notes on, 86
Relation of soils to prevalence of blight, 52
Resistant and immune chestnut stocks; search for, 32
Rockey, Keller E.; Report of public demonstration work, 57
Rumbold, Dr. Caroline; Experiments in chestnut tree medication, 48
Ruggles, Prof. A. G.; Report of results of special insect
investigations, 44
Sargent, Winthrop, Secretary of Commission;
final official report of, 9
Schock, Oliver D., Assistant Superintendent;
valuable co-operative work of the press acknowledged, 60
Scientific research; prompt and thorough work urged, 12
Scouting for the chestnut blight, 73
Shrawder, Joseph, Chemist; Report of chemical investigations, 47
Spot infections; procedure to eradicate, 73
Suggestions for information of chestnut timber owners, 38
Tener, Hon. John K., Governor; message to the Legislature
relative to the chestnut blight disease, 21
Topton Mountain, Berks county; study of blight conditions, 68
Treatment of infected timber and disposal of lumber, 38
Treatment of infected chestnut areas, 74
Tree surgery; examinations made and results of operations, 50
Unfinished work of Commission; experiments in progress and
work contemplated, 34
Utilization of blighted chestnut a serious problem, 54
Value of chestnut destroyed in Pennsylvania, 59
Williams, Hon. Irvin C., Deputy Commissioner of Forestry; Report
as Collaborator of Pennsylvania Department of Forestry, 17
Wentling, Prof. J. P.; Report upon utilization of blighted
chestnut, 54

Official Letter
to
Hon. John K. Tener
Governor of the Commonwealth of Pennsylvania

LETTER OF TRANSMITTAL.

THE COMMISSION FOR THE INVESTIGATION AND CONTROL OF THE CHESTNUT TREE BLIGHT IN PENNSYLVANIA

1112 Morris Building, Broad and Chestnut Streets

_Philadelphia, December 9th, 1913._
HON. JOHN K. TENER, _Governor,
Harrisburg, Penna._

_Sir_: We have the honor to transmit herewith our report of the operations of this Commission for a portion of the year 1913, this being also the final report of the Commission.

Eastern Asia, the home of the San Jose scale, has been found to be also the home of the chestnut blight. The disease has been found definitely in northeastern China; probably it is also present in Japan. There is no reason to doubt that it found its way to this country in the same way that the San Jose scale did, on nursery stock, and at about the same time, or perhaps somewhat later. Any system of strict inspection of imported nursery stock could have kept it out of this country, but no such system was then in use. It would probably not have been possible at that time to secure a law authorizing such inspection because of the lack of public appreciation of the seriousness of imported fungous and insect epidemics.

The oldest known spots of chestnut blight infection are in the neighborhood of New York City. Here again the disease could have been checked at an early date and never found its way into Pennsylvania, but nothing of the sort was even attempted. In fact, even up to 1911, no official work was done in New York upon the disease. In 1908 Murrill[1] advocated cutting out all chestnut trees within half a mile of diseased trees, but this plan was never put into practice in New York. In general, the greatest conservatism has prevailed regarding the seriousness of the disease. The view that the fungus was native to America, and its great virulence due to winter injury and other temporary climatic effects upon the trees, has been strenuously advocated. The Commission from the first, however, adopted the theory of the Department of Agriculture that the disease was of foreign origin and hence to be considered in the light of a dangerous invader. This view has since been amply justified. Pennsylvania was the first state to treat the epidemic seriously, but by the time the Commission was able to begin work the disease was spread over the eastern half of the State too completely to make its eradication there possible.

[1] Journal of the New York Botanical Garden, Vol. 9, No. 98, p. 30.

Twenty years ago such an epidemic as the present one would have attracted little attention, but now the prices of all classes of timber have been for some years increasing, and promise to continue to increase indefinitely. It is obvious that every possible care must be taken of the present forest stand; upon this point there is no longer disagreement. In Pennsylvania the chestnut is especially valuable, standing in intimate relation to many of the leading industries of the State. It is distributed throughout the State, comprising at least one-fifth, possibly one-third, of the timber. It is naturally adapted to poor, hilly land not suited for agriculture, and will produce profitable yields of extract wood, fence posts, rails, etc., in 25 to 30 years; and ties, poles, and saw timber in 40 to 50 years. Because of its comparatively rapid growth, its superior ability to perpetuate itself by means of sprouts, and the great variety of its uses, the chestnut may be considered the most important forest tree in the State. The ease with which chestnut can be managed according to the principles of forestry made it, before the appearance of the blight, one of the principal species depended upon to solve the problem of the future timber supply of the State. On steep slopes, where the per cent. of chestnut is high, serious deterioration, washing of the soil, and reduction in water supply will undoubtedly follow the destruction of the chestnut trees.

The complete loss of the present commercial stand of chestnut in Pennsylvania, which, now that the Commission has ceased work, seems absolutely certain, is a calamity which will be fully realized only in the future. In matters of this kind we have obligations to the future, aside from the particular emergency in hand. This is not the last tree disease that will sweep over the State. All efforts to control this disease would be justified even if we only learned how to control the next one. Methods which may not be practicable now will be highly practicable twenty years from now on account of the steady increase which is bound to come in timber values. The mere fact that this campaign against the chestnut blight has been undertaken at all shows a great advance of thought over that of previous years.

With these facts in mind, it is obvious that three courses were possible, when the extent and seriousness of the chestnut blight was first realized in Pennsylvania.

_First_,—Do nothing.

_Second_,—Conduct scientific investigations of the disease with the hope of determining by laboratory methods and very small field experiments some method of control.

_Third_,—Conduct scientific investigations, and at the same time immediately attack the epidemic by any and every means that seemed to afford any possibility of checking or even delaying the course of the disease. To follow the first method would have been to emulate simply the example of New York and New Jersey. The second course had many points in its favor, but it was obvious that such a course would yield no results in time to be used on the present epidemic, though possibly of the largest ultimate value. The third course appealed to the Commission as the only one possible under existing circumstances. The greatest handicap was the extent to which the disease was already present in the State.

In the eastern half of the State the disease was obviously beyond control. In the western half the best course available, and in fact the only method that has been proposed at all for control of the disease, was that of cutting out the advance infections. While this method is open to many criticisms, nothing better has been proposed even to the present time. The Commission adopted the cutting out methods advocated by the U. S. Department of Agriculture with two exceptions: (1). Spots of considerable size were cut out in some cases; that is, the cuttings were not limited to strictly advance infections. (2). No immune zone was established at first, although this might have been done later. The method was essentially that advocated by Murrill in 1908, except that trees were not cut to as great a distance as half a mile from the source of infection. Detailed reports of the cutting out work are appended. It is sufficient to say here that the progress of the disease in the western half of the State has been set back five years, and west of the line extending from Bradford to Somerset counties there is little infection, and what infection there is dates from 1913. There is no reasonable doubt that the disease could have been kept _instatu quo_ indefinitely, had the work of cutting out continued. As set forth in the appended reports, the methods of cutting out have been improved, the cost determined and reduced, and winter scouting established as a practical method. These methods developed by the Commission are now in active use in the States of Virginia and West Virginia, where the campaign of eradication is being vigorously pursued.

One of the most valuable results of the Commission’s work was the establishment of the fact that the wood of a blighted tree is entirely fit for use, and if utilized soon after the death of the tree from blight, can be disposed of in the regular way and at normal values. The Commission has advocated the cutting out of all diseased trees, since on account of the prejudice against blighted poles and timber, and the possibility of the market becoming glutted, this is the best plan. Also the cutting of diseased trees was urged because it would reduce the sources of infection. Since utilization was all that remained to be done in the eastern half of the State, the Commission secured a special reduced freight rate on blighted lumber, determined what demand there was in and out of the State for chestnut lumber and other chestnut products, and proceeded to bring owners and dealers together. This work had just reached the point of its highest efficiency when the Commission ceased work. As there is no longer any means of inspection and certification of diseased lumber, the reduced freight rate is no longer available.

When the Commission began work but few investigations had been made of the chestnut blight, and other States, as well as the U. S. Department of Agriculture, were working on the disease without special funds. The Commission by its example and by its direct efforts, assisted in securing Congressional and State appropriations, and practically all of the scientific work and all of the practical work which has been done on this disease since 1910 was made possible by the efforts of this Commission. A National law was passed which requires strict inspection of all imported nursery stock and the prohibition from entry of certain classes of stock, and which makes the repetition of such an event as the importation of the chestnut blight impossible, or at least highly improbable. The work of this Commission was one of the greatest factors in bringing about the passage of this law.

Not only has the work of the Commission aroused public attention throughout the Eastern States regarding this disease, but the public is awakened as never before by the example of the destruction of one species to the necessity of conservation of all timber resources. In this State the Commission has carried on a liberal educational campaign in which it has had the hearty co-operation of the State Forestry Department, the Conservation Association, such organizations as the Boy Scouts, various lumber and trade associations, and many other organizations, institutions, and individuals.

In conclusion, it seems necessary to call sharp attention to the real lesson to be learned from the chestnut blight epidemic—viz.: the necessity of more scientific research upon problems of this character; to be undertaken early enough to be of some value in comprehending, if not controlling the situation. We have seen that the blight might have been kept out of the country in the first place by inspection, or once in, that it might have been destroyed, or at least checked before it had gotten widely distributed. But instead it was permitted to enter, and to spread for many years without scientific notice, and for several more years without any organized attempt to control it, or even to study it seriously. Are we doing any better now with reference to the future?

China has been shown to be the home of the chestnut blight. China, then, would seem to be the obvious place to study it; but no pathologists are there, and state and federal parsimony has so far failed to provide for any investigations of the disease on its home ground by American pathologists.

It has been proposed to replace the chestnut in southern New England by plantings of white pine, in itself the most important eastern timber tree; but the white pine is in turn subject to a newly imported disease, the blister rust. It is not certain that very serious and united efforts are being made to investigate and control this disease even in the States that introduced it. As in the case of the chestnut blight, scepticism has even been expressed as to its seriousness. Again, it would seem that the obvious place to determine the seriousness of the blister rust was in Europe, its home; yet to date neither state nor National government has dispatched a scientist on this errand. In this connection it may not be amiss to call attention to the fact that in Pennsylvania there is, aside from the employees of this Commission, only one professional plant pathologist! Yet the preventable damage which this one plant disease—chestnut blight—has done, would pay for the work of more plant pathologists than are now at work in the entire world.

The Commission closes its work with regret, knowing well that the blight will now spread over the State without hindrance. There is some satisfaction in knowing, however, that the work left undone in Pennsylvania has been actively taken up in Virginia and West Virginia, and that the States of Ohio and North Carolina are making studies preparatory to combatting the disease as soon as it appears in those States. The scientific research carried on by the Commission will be continued by the U. S. Department of Agriculture. We may be certain that the war against this and other foreign epidemics will not cease until science is so far advanced in both theory and practice that they can be controlled.

Very truly yours,
WINTHROP SARGENT,
_Chairman_.

Report of
Hon. I. C. Williams
Deputy Commissioner of Forestry, Collaborator

A common mark of the blight. Small leaves which developed in the early spring on a top recently girdled by the blight, showing midsummer condition. Withered leaves above the canker; sprouts below.]

A HISTORY OF THE EARLY PENNSYLVANIA EFFORT TO COMBAT THE CHESTNUT BARK DISEASE.

BY HON. I. C. WILLIAMS, DEPUTY COMMISSIONER OF FORESTRY, COLLABORATOR, HARRISBURG, PA.

Preliminary to the final report of the Chestnut Blight Commission, it is thought desirable to make a statement detailing the history of the chestnut bark disease in Pennsylvania so far as known, and of the efforts to combat it, leading up to the formation of the Commission under the law of 1911, and the extended work of repression begun at that time.

The attention of the Pennsylvania Department of Forestry was first attracted to the appearance of the chestnut bark disease in this State by a letter from Mr. Harold Peirce, of Haverford, dated July 18, 1908, reporting its presence in Lower Merion Township, Montgomery County, and by an article appearing in the November, 1908, number of “Conservation,” from the pen of Dr. John Mickleborough, of Brooklyn. Subsequent correspondence with Dr. Mickleborough revealed the fact that he had been a student of the disease for over a year and had become familiar with it in all of its ordinary aspects. To these two gentlemen, therefore, the State is primarily indebted for the subsequent efforts made to study more particularly, and to attempt to control this vicious tree disease.

The facts relating to the discovery of the disease in America and its identification are pretty well known. It was first detected by Dr. Hermann W. Merkel, in the Bronx Zoological Park, New York City, in 1904, although it is almost certain that it existed in that neighborhood for probably more than a year prior to Dr. Merkel’s discovery. Referred for identification to Dr. W. A. Murrill of the New York Botanical Garden, he published a description of it in 1906[2], and by him the fungus was named _Diaporthe parasitica_, so called because it was believed to be the only parasitic species of the genus. The naming of the fungus has since been corrected by means of the researches of Anderson, Clinton, Farlow, Shear and Stevens, and it is now known systematically as _Endothia parasitica_.

[2] See “Torreya,” Vol. 6, No. 9.

Some controversy has been had over the origin of the disease and the case is probably not yet settled. Dr. Clinton’s contention is and has been, that it is a native fungus, which, by means of weather conditions and possibly other factors, has taken on new attributes. Dr. Metcalf, his co-worker Prof. Collins, Dr. Shear, and others believed and still maintain that it is of foreign origin, introduced into America by the importation of horticultural stock. Its first known appearance in the region of New York City and its spread in concentric zones from that point as a centre of infection, lent much plausibility to this theory. The recent discovery made by Mr. Frank N. Meyer, of the same fungus in northeastern China, where it is parasitic on _Castanea_, and where, it appears, the host trees have become rather highly resistant to its attack, leads further probability of correctness to Metcalf’s theory.

Possibly a great hope for America lies in this Chinese discovery. Pathologists and foresters are anxiously looking forward to the results of experiments now being made and which will be attempted, we hope, on a much larger scale in the future. The regrettable, ever-present fact is that this disease is with us here and now, and must be reckoned with from every angle of attack. There seems to be no present diminution sufficient to warrant the belief that it is likely to wear itself out, or that our trees will become sufficiently resistant to ward off the attack prior to the destruction of the trees themselves.

Subsequent correspondence between Dr. Mickleborough and the Department of Forestry culminated in a letter from him under date of March 9, 1909, in which he outlined a definite plan for the examination of a supposedly infected territory in southeastern Pennsylvania, and offered his services to the Commonwealth for carrying out plans of investigation. The proposed inspection was approved by the Department on March 17, 1909, and the services of Dr. Mickleborough thus enlisted. The first inspection visit was made by him in company with the writer, March 29, 1909, at Mt. Holly, in Cumberland county, but where no evidence of the disease was found at that time.

Prior to the beginning of this work in 1909, Dr. Mickleborough had been invited by Dr. Jane Baker, physician in charge of the Chester County Insane Hospital, to speak before an educational conference at Embreeville, Chester county. At this time the disease was not generally prevalent in that region, but a number of infected chestnut trees were found.

The work of inspection over the southeastern portion of the State thus undertaken under the direction of the Department of Forestry, as stated above, was conducted by Dr. Mickleborough, and carried through or into almost every county east of the Susquehanna. During the progress of this examination the chestnut blight was not found north and west of the South Mountain, although prior to this time the United States Department of Agriculture had reported the existence of two spot infections in the western portion of the State, near Altoona, and a re-examination of the material relating thereto by Dr. Metcalf and his assistants, seemed to leave no doubt as to the correctness of this report. Certain it is that in May, 1909, there was no large or extended infection west of the Susquehanna. Had there been in existence at that time the means to carry on work of control along both sides of the Susquehanna River, who can tell what the result might have been, looked at in the light of our present knowledge?

The report of Dr. Mickleborough’s inspection and study was published by the Department in the autumn of 1909. This is a 16 page pamphlet illustrated by drawings showing a portion of the structural formation of the fungus, and by a Lumiere color photograph of a stem section of chestnut covered externally by the fruiting fungus. This specimen of infected chestnut wood was sent in from Pike county, in the upper Delaware valley, and was incubated and developed in a moist cell in the Department of Forestry during the summer of 1909.

In the early part of the study of this bark disease, it was believed that the Japanese species of _Castanea_ was either immune or highly resistant to attack. Several specimens of Japanese chestnut were under observation on Long Island, and fairly gave rise to this belief. One grove examined near Westbury, in June, 1909, showed the Paragons and common chestnuts badly attacked. The Japanese showed no attack at all.

Through the courtesy of the Hicks nursery at Westbury, forty-five young chestnut trees supposed to be Japanese, and one hundred grafting scions were sent to the chestnut orchard of Mr. Levi Wise, at Gap, Lancaster county, Pennsylvania, and distributed among four persons of the neighborhood for planting and testing out for immunity. The bark disease was at that time particularly prevalent in the chestnut woods at this place. Some of the newly planted trees died from other causes, but enough of them were attacked and killed by the blight to show that these particular trees, at least, were not immune.

On the 29th day of March, 1910, Dr. Mickleborough delivered a lecture on the subject of this tree disease before the Main Line Citizens’ Association at the Merion Cricket Club, Haverford, Pa. This meeting was arranged largely through the efforts of Mr. Peirce, who at that time was the owner of several acres of chestnut woodland, and of which tract Dr. Mickleborough made a rather extended examination, finding the chestnut blight present in a number of trees. This discovery and the lecture delivered on the subject brought the matter prominently to the attention of the citizens of that neighborhood, and later led to some very important developments with respect to studying and combating the disease.

Following this address by Dr. Mickleborough, Mr. Peirce was in correspondence with the Department of Forestry, calling attention to the inroads being made upon the chestnut trees by this disease in the neighborhood of his residence, requesting the Department to render such help as it might be able in assisting the people to understand the situation better, and, if possible, to eliminate or at least attempt to control the trouble. This correspondence culminated in the calling of a meeting on May 23, 1910, at the house of Mr. Robert W. Lesley, at Haverford, which was attended by a number of the residents and land owners of the neighborhood, by Dr. John W. Harshberger, the botanist, representing the University of Pennsylvania, and by the Deputy Commissioner, representing the Pennsylvania Department of Forestry.

The preliminary arrangements for beginning an extensive survey of this region were discussed at this meeting. The Department representative made his report to the Forestry Commission at its meeting held on June 3, 1910. On motion of Dr. Rothrock, the Commission directed that the Department render the desired help, and on the same day a letter to this effect was sent to Mr. Peirce, the secretary of the citizens’ meeting. On September 1, 1910, a corps of inspectors from the Department in charge of the Deputy Commissioner, arrived at Haverford and Ardmore, prepared to begin their work. Offices were speedily fitted up in the building of the Merion Title and Trust Company at Ardmore, and the first inspection of trees was made on the property of Mr. Lesley on Saturday, September 3rd. From this date forward until December 19, 1910, the work was vigorously carried on, and a close inspection made of 296 properties, covering most of the region extending from Overbrook to Paoli, and from the Schuylkill River on the north, to a considerable distance south of the Pennsylvania Railroad. A draft of each property was prepared showing the location of all chestnut trees and indicating those which at that time were apparently free of disease, as well as those showing the infection. Each property owner was then furnished with a copy of the report and draft relating to his own land.

To show the interest taken in this work by members of the Main Line Citizens’ Association, it is necessary only to state that the work was carried on almost entirely at the expense of the association. The individual contributions for the purpose amounted to $2,707.70.

During the progress of this inspection, a second public meeting was held in the auditorium of the Merion Cricket Club, at which time a preliminary report was submitted and discussion had with respect to the situation as it then existed. This meeting was attended by a large number of ladies and gentlemen, members of the association, and much interest was shown in the progress reported. The final report of the committee of the association having the work in charge was printed and rendered to the members under date of May 8, 1912. This committee was as follows: Messrs. Harold Peirce, Chairman; Theodore N. Ely, Allan Evans, Edgar C. Felton, William Righter Fisher, Alba B. Johnson, and Robert W. Lesley.

In a letter bearing date the 12th day of March, 1909, addressed to the Commissioner of Forestry at Harrisburg, Dr. Mickleborough used this language. “As to remedy, the best that can be suggested by anyone at present is _Control_ and not _Extermination_, for various reasons. This I think is also true of the San Jose scale.” It will thus be seen that the original idea involved in the attack on the chestnut blight in Pennsylvania was _control_, just as the Department of Agriculture of this State has always aimed at _control_ of the San Jose scale, suggested in the letter just quoted. After the preliminary studies were completed, no one believed that extermination or eradication could be accomplished with the means at hand; but it was thought then, and is still the belief of those who are most closely associated with the work, that a _control_ is possible, and that it was much more possible then than now, after the lapse of a period of five years.

During the progress of the inspection along the Main Line, it became apparent that more than a local effort was demanded if any substantial progress were to be made towards preventing the spread of the disease. Steps were taken to enlist the active interest of the Governor and the Legislature, (then in session). On the evening of April 10, 1911, Governor Tener sent a special message to both houses of the Legislature, calling direct attention to the situation, and asking the help of the General Assembly to combat the disease. The Governor’s message was as follows:

“Commonwealth of Pennsylvania,
“Executive Chamber,
“_Harrisburg, April 10, 1911_.

“Gentlemen of the Senate and House of Representatives of the
Commonwealth of Pennsylvania:

“I have the honor to call your attention to a new and
virulent disease of the wild chestnut tree, commonly known
as chestnut blight, recently discovered near New York City,
and hitherto unknown in America. The disease has continued
to spread, destroying the chestnut trees in the neighborhood
of New York City and well up the Hudson. It has invaded Long
Island, beginning at the western end, sweeping eastward,
practically covering the island. It has progressed to the
southwest, through the whole of the State of New Jersey,
and all the chestnut trees there appear to be doomed to
destruction. It has entered Pennsylvania and is prevalent in
the Delaware Valley. It has been discovered in the following
counties: Pike, Monroe, Northampton, Bucks, Montgomery,
Chester, Philadelphia, Delaware, Lancaster, and southern
Berks. In isolated places it has crossed the Susquehanna,
and is now detected in eastern York, eastern Perry and one
portion of southwestern Perry. Other points of infection
have been found near Altoona and Greensburg.

“Experiments made by the Department of Agriculture at
Washington demonstrate that it is possible to prevent the
spread of the disease by removing spot appearances as they
are detected, and destroying the trees in which the disease
occurs. By this means the region around Washington has
been freed from the blight for at least two years, and it
has not re-invaded this area. In the southeastern portion
of Pennsylvania, where the infection is severe and almost
complete, little hope exists for saving the trees, but in
that portion of the State west of the Susquehanna and north
of the Blue Mountains, it is hoped, by prompt action on
the part of the State, to prevent further damage. If this
disease can be held within the southeastern portion of the
State, it will mean the saving of the wild chestnut trees
in the other parts of the Commonwealth, the value of which
extends into the millions of dollars.

“I therefore recommend that the Legislature give immediate
attention to this important subject and that a Commission be
created with sufficient power and appropriation of moneys to
determine upon and employ efficient and practical means for
the prevention, control, and eradication of this disease,
and that said Commission be authorized, in conjunction
with the Department of Forestry, or otherwise, to conduct
scientific investigations into the nature and causes of such
disease and to adopt such means to prevent its introduction
and spread as may be found necessary.

“JOHN K. TENER.”

The next day, April 11, 1911, a bill having this purpose in view, and which had been previously carefully drawn and vigorously criticised, was simultaneously introduced in both House and Senate. This bill became a law by the signature of the Governor, June 14, 1911[3]. The law creates a Commission of five members and vests them with almost plenary power to carry out its mandates. An appropriation of $275,000 became available at once. The appointment of the members of the Commission followed after an interval of about two weeks. Organization was effected, officers and assistants chosen, and on August 23, 1911, the Commission was prepared to proceed with its work.

[3] See Pamphlet Laws, 1911, page 922.

While the major effort of the Commission from the beginning was to get a control, the subject of eradication was vigorously debated, and, as will be seen in subsequent pages, determined efforts at eradication were undertaken under the advice and direction of the Commission. The feeling was that if there be any merit in such effort, opportunity ought not to be lacking to prove it. The early announced and decisive plan involving the cutting-out method, proposed and outlined by Dr. Murrill, contributed very considerably toward the decision to try out this method.

The Murrill plan ([4]) was as follows:

“Owners of standing chestnut timber within the affected area are advised to cut and use all trees, both old and young, that stand within half a mile of diseased trees, unless protected from infection through wind-blown spores by dense forest growth or some other natural barrier. This may not prevent the spread of the disease through the agency of storms, birds and squirrels, but it will at least retard its progress. Old weathered chestnut trunks that have been dead several years have no power to spread the disease, and these may be cut at leisure for the tannic acid factory or for firewood. Trees of good size recently killed should be turned into lumber as soon as possible; the fungus affects only the bark, but other fungi may afterwards impair the value of the wood if allowed to stand too long. Discarded branches and young trees of no value that are cut near the edge of the infected area should be burned at once in order to destroy the spores they contain; but if they are well within the zone of infection, such precaution is useless.”

Every element in the Murrill plan has been employed both by the Commission and by the State Department of Forestry. The fact that subsequently Dr. Murrill partially shifted his ground[5], did not seem sufficient reason to warrant the abandonment of a plan of attack which in many cases was productive of satisfactory results.

The history of what work the Commission did, and of the results accomplished form the substance of several preliminary reports submitted to the Governor from time to time. The final report is what follows.

[4] W. A. Murrill: Journal of the New York Botanical Garden, Vol. 9, No. 98, p. 30. February, 1908.

[5] Harrisburg Conference Report, 1912, pp. 194, 201, 202.

Report of
Mark A. Carleton
General Manager Pennsylvania Chestnut Tree
Blight Commission

Summer condition of a blighted tree. The withered leaves of the top above the canker, and the vigorous sprouts below the canker are characteristic signs.]

THE FIGHT TO SAVE THE CHESTNUT TREES; FINAL REPORT OF THE GENERAL MANAGER.

By MARK A. CARLETON, GENERAL MANAGER, PENNSYLVANIA CHESTNUT TREE BLIGHT COMMISSION.

In closing the active work of this Commission, it is a great satisfaction to be able to report constant progress to date, and the attainment of good, practical results. The work began two years ago in the midst of much skepticism as to its possibilities, but the optimism of the Commission and the wisdom of its methods of operation have in the main, been amply confirmed by the results since obtained.

PROGRESS OF FIELD WORK.

A more or less definite division has been maintained between the slightly infected Western portion of the State and the badly infected Eastern portion, known respectively as the Western and Eastern districts. In a previous report it was stated that in the Western part of the State the blight had been eradicated to the extent covering nearly one-half of the area of the State. This area so far as is known to date has been maintained free from the disease. In a few cases new infections were found which have been removed. It is important to note in this connection not only the fact that the progress of the disease has been checked in Western Pennsylvania, but that we have without much doubt prevented the blight from gaining a foothold in Ohio, and nearby portions of New York and West Virginia.

In the Eastern District since January first of this year, the field work has developed almost entirely into a campaign of utilization, no rigid sanitation work having been conducted except for the protection of chestnut orchards and nurseries.

EFFECTIVENESS OF THE CUTTING OUT METHOD.

In the two years work no facts have yet been obtained which would indicate the advisability of any change in our present method of “cutting out” diseased trees and thorough cleaning of the stumps for the eradication of the disease. A number of tracts where the disease has been eradicated by Commission employees have again been inspected recently, giving results, which are in the main, favorable. Of course, improvements have been made as to details all along. It is not a pleasant prospect to consider the serious results likely to follow after this method of eradicating the disease, conducted by the Commission, is obliged to cease.

BENEFICIAL INSECTS.

It will be of interest to quote here the words of the Forest Entomologist, of the U. S. Department of Agriculture, in his comment on a widely disseminated press notice of that Department, November 22nd, 1912, apparently based on the work of F. C. Craighead.

“The beneficial work of these insects can, however, be greatly encouraged if the owners of the timber will dispose of the diseased trees in the principal centers of infection, as recommended by the Chestnut Blight Commission of Pennsylvania, and other State and Federal officials. Thus, if the large majority of the infection is disposed of, the beneficial insects will concentrate on the remaining scattering and isolated infections, and thus more completely destroy the fruiting bodies and contribute to the protection of the remaining living trees. In fact, it is a question of the owner securing the greatest benefit from the natural agencies of control by doing his share of the work.”

NURSERY INSPECTION.

The inspection of nursery stock has been made even more rigid than before. Not only has it been required that every individual tree should be inspected by a competent employee of this Commission, but in shipping it has been required also that every individual tree should be tagged. A copy of the revised regulations governing the inspection and shipment of nursery stock is appended to this report, which shows the form of tags required to be attached both to individual trees and to bundles of trees. The fact that several of the most serious infections in the State have been caused heretofore by the planting of diseased nursery stock in new localities is sufficient reason for so rigid an inspection.

DISCOVERY OF THE CHESTNUT BLIGHT IN CHINA.

It has recently been proved by authentic specimens and artificial cultures of the material transmitted by the Explorer of the U. S. Department of Agriculture, that the chestnut blight exists in Eastern China.[6] This fact makes it all the more probable that the beginning of the disease in this country may have come about by the introduction of such diseased stock from China or Japan. That new centers of infection are often started by the introduction of diseased nursery stock, is a common observation.

[6] Science, Vol. 36, No. 937, p. 825, Dec. 13, 1912.

PROTECTION OF ORCHARDS AND NURSERIES.

It has been the policy of the Commission for sometime to protect orchards and nurseries from outside infection in all cases where the owners have expressed a desire for such protection, and have themselves taken care to control the disease as much as possible. This work has been successful much beyond our expectations. The largest and most important orchards thus protected are located at Sunbury, Paxinos, and Berwick. The owners of neighboring forest tracts have been required to remove all diseased chestnut trees within one-half mile of the nearest point of the orchard in each case. An interesting result in one of the most important of these cases is the fact that these owners have been able to sell the products of their diseased trees for an amount considerably above the entire cost of removal, sanitation work, etc.

PREVENTION OR REMEDY.

At this writing no specific remedy has been found for the disease. However, later information confirms the statements previously published that the disease may be largely prevented from entering healthy trees by constant and regular spraying with Bordeaux Mixture made up in proportions of 5 pounds of lime, 5 pounds of copper sulphate, and 50 gallons of water. The application of this mixture simply prevents any new germination of spores, but has no effect whatever, in cases where the disease has already started in the tree. Because of the cost, it is, of course, not applicable in forests.

CONTROL OF THE DISEASE IN ORCHARDS.

By cutting out the cankers and coating with antiseptic solutions and water proofing afterwards, the blight can be fairly well controlled in chestnut orchards and in certain valuable lawn or park trees. In connection with this treatment a spray of the Bordeaux Mixture as above noted should be used occasionally. Excellent results along this line of experiment are shown in a large orchard at Paxinos, and in several of the public parks of the State.

FAKE TREATMENTS, THEORIES OR CAUSES, ETC.

As often happens in the case of a public campaign against a serious epidemic, we have been constantly besieged by the gratuitous offers of various and sundry remedies for the blight, which include applications of fertilizers to the soil, insertions of flowers of sulphur and other compounds in holes bored in the trees, applications of coatings of different chemicals to the body of the tree, and numerous other treatments, all of which we believed in the beginning to have no value. However, all parties having theories to advance or remedies to propose have been given a chance to prove their claims by experimenting on trees controlled by the Commission for such purposes at Emilie, Bucks county. A number of parties have taken advantage of the opportunity. Recently, an examination was made of the various treatments by a competent Board of Reviewers, whose conclusion was that not one of the treatments tried had any deterrent effect upon the chestnut blight.

Many of the persons above mentioned were apparently sincere in the claims they made, and were simply ignorant of the true cause of the disease. Instances have come to our attention, however, of parties practicing certain methods of treatment and charging for the same, who are plainly impostors. Employees of the Commission have no doubt benefited many people by exposing the methods of these impostors.

EXAMINATIONS OF INDIVIDUAL TREES.

Excellent opportunities have been afforded the tree surgeon of the Commission and his assistants to counteract the influence of false theories and worthless remedies such as above mentioned, in responding to the numerous requests for the examination of individual trees. These requests have continued to come to the Commission headquarters right up to the time of closing our work. No other line of work has been so effective in arousing the personal interests of the people. No request from any part of the State has been ignored. In this connection much incidental advice has been given to property owners as to the general handling of lawns and orchards, and the management of small woodlots.

PUBLIC PARKS AND FARMS.

In co-operation with the officials of Wildwood Park, at Harrisburg, the Commission has completely eradicated the blight from that Park, about 150 diseased chestnut trees having been removed or treated out of a total of 1,290 trees. Here in a few cases the peeled stumps were creosoted to show that method of sanitation. Considerable help has also been given to the management of Fairmount Park. Arrangements have also been made for the entire removal of blighted chestnut trees from the State Live Stock Board’s Farm, in Delaware County. In the event of the continuation of our work, it was also planned to eradicate the blight thoroughly from the Valley Forge Park grounds.

BLIGHT-EATING BEETLES.

It has been announced by the Bureau of Entomology, U. S. Department of Agriculture, that several species of beetles have been found eating the spores of the blight fungus, and it is stated that “should these insects prove as beneficial as the observations indicate, they are certain to be an important factor in the natural control of the dreaded chestnut blight disease.” It is worthy of note in this connection that the insect investigations of this Commission have shown that a number of insects also carry large quantities of blight spores, and may thus indirectly assist in the dissemination of the blight. One of these insects which was found to carry an enormous number of spores is one of the beetles above mentioned as eating the fungus.

CORDWOOD AND THE SPECIAL TARIFF.

Since writing the last report, there has been a considerable shipment of chestnut cordwood, shippers taking advantage of the special tariff issued by the Pennsylvania Railroad. At last accounts the prospects were that there would be much business in this line right along in the future, being encouraged by the special low rates.

PROMPTNESS IN UTILIZING CHESTNUT.

Observations made by Commission employees in company with commercial lumbermen have shown that already in certain localities, diseased chestnut has been dead so long that deterioration is beginning. We have, therefore, made it plain to owners of such chestnut and have advertised the fact as much as possible, that promptness is necessary in getting rid of the diseased trees, if the owners wish to obtain the most value possible from the trees.

INTENSIVE LOCAL UTILIZATION.

Our most difficult line of work has been that of utilization. Facts as to the conditions could easily be obtained, but the difficulty has been in bringing the buyer and seller together. Recently a plan was adopted, which if we would be able to continue its operation, would without question, hasten very rapidly the utilization work. This plan, the details of which are given elsewhere, is to canvass particular localities thoroughly, finding out just what can be offered in the way of different chestnut products, ascertaining the local market for the same, and then determining so far as possible, where else the surplus may be marketed. In connection with the carrying out of this plan, up to this writing as many as a dozen portable saw mills have been located in one county, and in other localities many practical operations had already been started, thus tending to rapid and clean cut work in utilizing blighted chestnut.

RESISTANCE AND IMMUNITY.

The discovery of the chestnut blight in China makes it now all the more probable that resistant chestnut stocks may be obtained in that country. It was, therefore, a wise movement last fall when we took advantage of the opportunity to obtain a considerable amount of seed of what is probably the most important chestnut in Eastern China. A large quantity of the nuts were planted at Paxinos, and the seedlings at this date which are from six to fifteen inches high, are looking well. From the nuts sent also to the State Forest Nursery at Greenwood, 75 seedlings are at present growing, and from those sent to Asaph, Pa., there are now 182 plants, averaging ten inches in height. All of these seedlings will be of much value in cross-breeding and other ways in the important future work of developing blight resistant orchard trees. In this connection it should be noted that in a recent bulletin issued from the Arnold Arboretum a considerable discussion is given of the possibilities in developing blight resistant chestnut trees from Chinese introductions, a number of the latter now being grown at the Arboretum. The two mentioned as the most important include the one of which we now have seedlings. So far these Chinese chestnuts grown at the Arboretum have not become blighted.

According to the Kew Index, there are seven species of chestnut and twenty-one of the chinquapin in the world. From all these species there should be many other chances of obtaining blight resistant trees that may be used in breeding and making our own stock better.

CHESTNUT BLIGHT EXHIBITS.

Several exhibits of specimens showing the work of this Commission have been placed in public institutions which will remain as monuments of our work. An excellent exhibit has been placed at the Carnegie Museum at Pittsburgh. Another has been finally completed in the State Museum at Harrisburg, and a third one at the Commercial Museum in Philadelphia is not yet finished, but has been planned on rather a large scale. It was contemplated also to place another exhibit in the Everhart Museum at Scranton, which may yet be done. An excellent exhibition of specimens and illustrations of our work was made in connection with the State Forestry Exhibition at Horticultural Hall, Philadelphia, in May.

PUBLICATIONS.

When this final manuscript is published, there will have been issued the following publications of this Commission:

Report of The Pennsylvania Chestnut Blight Conference. (Unnumbered).
Bulletin No. 1—The Chestnut Blight Disease.
Bulletin No. 2—Treatment of Ornamental Chestnut Trees Affected
with the Blight Disease.
Report of the Pennsylvania Chestnut Tree Blight Commission,
July 1st to December 31st, 1912. (Unnumbered).
Bulletin No. 3—Field Studies in Blight.
Bulletin No. 4—Chestnut Blight Fungus and a Related Saprophyte.
Bulletin No. 5—The Symptoms of Chestnut Tree Blight and a
Brief Description of the Blight Fungus.
Bulletin No. 6—The Chestnut Tree. Methods and Specifications
for the Utilization of Blighted Chestnut.
Bulletin No. 7—Morphology and Life History of the Chestnut
Blight Fungus.
Final Report of the Chestnut Tree Blight Commission. Numerous
descriptive and educational circulars, charts, etc.

CO-OPERATION.