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At the suggestion of Professor Smith, Prof. F. L. Nason of the 

 New Jersey Agricultural College, New Brunswick, N. J., has 

 conducted a series of investigations concerning the composition of 

 Eaupenleira, and has at last succeeded in preparing a substance 

 almost identical with the foreign product. Professor Nason's 

 compound is known under the name of " dendrolene," and is 

 nearly if not quite as effective as the Raupenleim. It may be pur- 

 chased at about six cents per pound, and is well worth a trial in 

 protecting trees against canker-worms. 



While this paper is intended to treat of insecticides rather than 

 insects, a few words additional concerning the application of some 

 of these methods in combating the canker-worm and tussock moth 

 may not be inappropriate, since these insects have been unusually 

 abundant in many parts of the State this year. 



The apple orchards of eastern Massachusetts were, as a rule, 

 seriously damaged by the canker-worms, and in some orchards the 

 fruit crop was almost a failure from this cause. The ravages of 

 this pest can be obviated by banding the trees with Raupenleim or 

 tar, as already indicated, to prevent the ascent of the female moths. 



The canker-worms being of two kinds, fall and spring, this work 

 should be done early in the fall and the bands kept fresh up to the 

 time severe cold weather sets in, and should also be put in work- 

 ing order with the advent of warm weather in the spring. The 

 wingless female moths ascend the trees on warm days to lay their 

 eggs, and the same weather that will bring them out will also soften 

 the bands — if they have been properly put on — and make them 

 sufficiently adhesive to catch the moths. 



The value of the presence of chickadees in orchards has been 

 ably demonstrated by the ornithologist of the Board, Mr. E. H. 

 Forbush, in a recent bulletin. These birds, as has been pointed 

 out by Mr. Forbush, destroy immense numbers of canker-worm 

 moths and eggs, and may be made to frequent orchards by placing 

 meat, bones, etc., in the trees during the winter. Where these 

 precautionary measures have been neglected and the canker-worm 

 larvae appear in the trees, spray promptly and thoroughly with 

 arsenate of lead, as directed. 



Against the tussock moth, which has caused so much damage 

 this year to parks, street trees and even small orchards in Boston 

 and the suburban district, as well as elsewhere in the State, some- 

 what different methods should be employed. The present year the 

 pest devastated many fine elms on Boston Common and stripped 



