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growing in parks or in rows with American elms. Such a course, how- 

 ever, would seem to be undesirable. After the elm leaf-beetle has 

 established itself in a given locality, it will attack the American elms 

 to a very serious extent, in the absence of its favorite food plant. It 

 is, therefore, better to allow a few European elms to remain. These 

 ■will then act as trap trees, and the necessity for treating a large 

 number of trees will in most cases be greatly reduced. 



In selecting shade trees, particularly for small cities and towns in 

 agricultural regions, and even to a considerable extent in large cities, 

 the relative honey-producing qualities of the proposed shade trees is 

 a matter of some little importance; not so much, perhaps, in the mat- 

 ter of actual food for the ordinary honeybee as in that of the increase 

 of bees on account of their great value as cross fertilizers of orchard 

 trees and forage crops. From this point of view, there are five very 

 important honey producers among the principal shade trees. These 

 are, in order of importance: American linden, tulip tree, black locust, 

 horse-chestnut, and sugar maple. 



GENERAL WORK AGAINST SHADE-TKEE INSECTS IN CITIES AND 



TOWNS. 



The question of proper work against the insects which affect shade 

 trees in cities and towns naturally divides itself under two heads: (1) 

 What can be efficientlv and economically done by city governments? 

 (2) If city or town administrators will not appropriate a small amount 

 of money to carry on work of this kind, what can citizens who are 

 interested in the preservation of shade trees do ? 



The planting of shade trees seems to be considered a legitimate func- 

 tion of the board of public works in every municipality. It is some- 

 times done by a specially appointed officer, under the control of the 

 superintendent of streets and sewers; or it is placed in charge of a 

 subcommittee of the board, or a special commission of outsiders is 

 appointed to superintend the work. Admitting that the planting of 

 shade trees is a public matter, their care should also be a public duty. 

 Yet in not one of the larger or smaller cities of the Eastern United 

 States with which the writer is familiar is any proper amount of work 

 done by the public authorities against shade-tree insects. New Yorkis 

 the only city in the country where a man of entomological knowledge 

 is employed to direct operations against shade-tree insects, either in the 

 streets or the public parks. The writer does not wish to be understood 

 as advocating the appointment of a paid entomologist by every city 

 government, although where the parks are large in cities situated 

 within the region of greatest shade-tree insect activity, such a course 

 is always desirable. With an intelligent and industrious superintend- 

 ent of parks, or a city forester, or whatever he may be termed, and the 

 wise expenditure of a comparatively small amount of money each year, 

 the shade trees of any city could be kept green throughout the summer. 



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