LOANS AUTHORIZED, BUT NOT ISSUED. – Concluded. * Inside of Outside of Date of Order. Object. Debt Limit. Debt Limit. Brought forward . . . . . . . . . . . . . . . $3,553,101 00 $2,859,000 00 A COMMUNICATION FROM THE SUPERINTENDENT OF PUBLIC GROUNDS RELATIVE TO EXTERMINATING THE ELM BEETLE. MAYor's OFFICE, BoSTON, MASS., 5 August, 1901. To the Honorable the City Council : GENTLEMEN, - A communication from the Superintendent of Public Grounds, giving the results of his investigation as to the most effective means of exterminating the elm beetle, is enclosed. This report deals with a matter of public interest and importance, and should be printed as a City Document. Respectfully, CITY OF BosTon, PUBLIC GROUNDS DEPARTMENT, BoSTON, July 31, 1901. HON. THOMAS N. HART, Mayor of Boston : DEAR SIR, - On July 18 you called my attention to a communication referred to you by Chairman Charles E. Stratton, of the Park Department, from the Superintendent of that Department, in which he called attention to the ravages of the elm-leaf beetle in Jamaica Plain, and suggesting means of eradicating it. I may state in this connection that several months ago I requested the Police Commissioners to instruct patrolmen in all parts of the City to notify me of any cases that came under their observation where caterpillars or other parasites were found preying upon the foliage of the street trees, and the men of my Department were particularly enjoined to notify me if any dangerous parasites appeared upon the trees on the parks and squares in my Department. As a result of these precautions I had already been admonished of the appearance of this dangerous pest upon the elm trees in this vicinity, and had taken such measures as I deemed called for to meet the threatened evil. In my letter to you of July 19 I promised to get all the facts I could concerning the elm beetle, and have extended my inquiry for this purpose. I find that in Jamaica Plain there have been, on ten streets, twenty-three trees infested with the elm beetle, and on private grounds, thirty-eight. In Dorchester, on ten streets, one hundred and twenty-nine trees were infested, and on private grounds, seventy-three. In Roxbury, on two streets, only nine trees were infested. Thus we have a total of one hundred and sixty-one street trees and one hundred and eleven trees on private grounds in Boston, so far as can be ascertained up to this date, which have been infested with the elm-leaf beetle. It appears that, according to A. H. Kirkland, Assistant Entomologist of the Massachusetts State Board of Agriculture, the elm-leaf beetle, which is an imported European insect, began its depredations in the Connecticut Valley in 1895, and at Springfield and Northampton it has been quite destructive, and later at Groton it duplicated the damage caused at these places. I have found, also, that it has made its appearance at Worcester before this year, and seems to be gradually but surely spreading. Mr. Kirkland says: “That this insect will prove a serious pest in the near future in many of our larger cities seems the only conclusion to be drawn from the experience of other States, notably New York and Connecticut. It attacks, and if neglected, kills our most valuable species of shade tree, and is slowly but surely spreading over the State.” According to this authority the elm-leaf beetle appears to have entered Massachusetts from the South several years ago, and has gradually spread northward along the Connecticut and Housatonic rivers. A lateral diffusion of the insect, it appears, is now taking place in the valleys of the streams contributing to these rivers, and probably along the main lines of our railroads. It would appear, from the authority quoted and from other sources of information, that, though Boston and its vicinity has been wonderfully preserved from its ravages, it is now closing in upon us from various directions, and it would appear to be absolutely necessary for us to consider how we shall fight the pest, and, having ascertained the best methods, devote ourselves intelligently to the work of extermination. Before considering measures of repression, however, it would be well to know something of the nature and habits of the elm-leaf beetle. According to Mr. Kirkland, “the mature beetles pass the winter in various sheltered places, under clapboards, in buildings, etc., in some cases crawling into houses in such great numbers as to cause much annoyance. In this region they emerge from the first to the middle of May and feed greedily upon the elm, eating innumerable shot holes in unfolding leaves. Egg-laying commences in a few days and extends over several weeks. Of two female beetles observed by Dr. Felt, one deposited 431 eggs in 27 days, the other, 623 eggs in 28 days. The eggs are spindle-shaped, orange yellow in color, and are laid in irregular rows on the undersides of the leaves in much the same manner as the eggs of the potato beetle, an allied insect. The young larvae emerge in about one week (from late in May to the middle of June) and attack the under surface of the leaves, gnawing away the epidermis and causing the leaves to turn brown. From two to three weeks are required for the completion of the larval stage, at the end of which period they are about one-half an inch in length, of yellowish color, with a dark-brown or black stripe on either side. They then descend to the rough bark of the tree or to the ground and transform into pupae. From five to ten days are spent in the pupal stage, varying according to the temperature, when the mature beetles emerge, feed, pair, and lay eggs for a second brood, which matures in the late summer. The beetle is from one-fourth to three-eighths of an inch in length, pale yellow, with a black stripe on the outer part of each wing-cover.” “This insect,” according to the same authority, “feeds upon both the European and the American elm, naturally preferring the former. In many cases, notably at Northampton, where European elms stand in close proximity to American elms, the former are badly injured, while the latter are practically unharmed. When the European elm is not available, however, the American species is readily attacked and severely injured. At Groton last summer numbers of large American elms were so severely injured that they were as brown as if scorched by fire. At Springfield several American elms that were stripped three years in succession are now in a dying condition. Dr. Felt states that the Scotch elm also suffers seriously from the attacks of this insect.” In my letter of July 19 to your Honor, I said I would strongly recommend that spraying the trees be stopped immediately, as this method serves to scatter the pest to places which it would not otherwise reach. What I meant by this was that at this stage of growth of trees the mere act of spraying was useless; that, as I wrote to the Mayor of New Haven two years ago on the subject of destroying leafconsumers, the spraying of trees at this season of the year was simply a waste of the City's finances. But that there is a time when spraying would be effective and should be resorted to is one of the things which all old gardeners very well know. They know by long experience the truth of the adage that an ounce of prevention is worth a pound of cure. Let me cite a case in point. All have noticed that the rose trees on the Public Garden are clean, and their foliage never disturbed by slugs and other insects which usually prey upon such shrubs. This is prevented by a method of spraying well known to the profession. We make an emulsion of whale oil soap, lime, and sulphur, and by the agency of a syringe thoroughly spray the plants before the leaves come out. This not only cleanses them, but destroys whatever eggs or insects there may be on the stems or in the ground at their roots. By adopting this simple precaution we find that we have no trouble with the insects; whereas, should we neglect it until the leaves developed, we would fight the pests at a disadvantage, and in trying to kill the insects we would be most apt to kill the plants, and even then we would not get rid of the slugs. Let me further illustrate my point. Every greenhouse man of experience knows that by fumigating his greenhouse once in every two weeks he will not be troubled by the aphis or red spider, or the green fly. But if he neglect this precaution, and these pests once get ahead of him, they will destroy the foliage and defeat his efforts for their destruction. The lesson he learns — sometimes by costly experience — is, that not only is an ounce of prevention worth a pound of cure, but that what is worth doing at all is worth doing well. From these facts you will understand the position which I take in the matter of spraying trees. After the leaves on them have grown and the beetles have become domesticated on them it is only waste of time and money to strive to kill them by spraying. But as I have shown, spraying at the |