Xo. 4.] IXSECTICIDES. 371 



The value of the presence of chickadees in orchards lias 

 been ably demonstrated by the ornithologist of the Board, 

 Mr. E. II. 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 meas- 

 ures 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 or- 

 chards in Boston and the suburban district, as well as else- 

 where in the State, somewhat different methods should be 

 employed. The present year * the pest devastated many fine 

 elms on Boston Common and stripped and in some cases 

 seriously damaged numerous street trees. Many horse- 

 chestnut, elm, pear and cherry trees stripped in midsummer 

 by this insect in Boston, Chelsea, East Boston and Charles- 

 town have been unable to throw out a second crop of leaves 

 (like the linden) and are as bare as in winter. To prevent 

 the ravages of this pest in the cheapest and most efficient 

 manner the infested trees should be thoroughly cleaned of 

 the nests in the winter when the branches are bare. These 

 nests, from their white, frothy appearance, are readily seen 

 and easily removed. Where they occur in crevices in fences 

 and in other places difficult of access, they may be destroyed 

 by the use of crude mineral oils. After the larvae hatch, 

 trees where they are most abundant should be heavily 

 sprayed with arsenate of lead wherever it is practical to do 

 so. In the same way, so far as possible, trees which have 

 been cleared of nests should be isolated from infested trees 

 by means of Raupenleim or other suitable bands, those in 

 public places being put on at a sufficient height from the 

 ground to prevent injury to the clothing of passers by. 

 These methods, if thoroughly enforced, will reduce the 

 numbers of the pest in localities where employed to a point 

 where it will do no particular damage. 



* 1895. 



