THE WILLOW BORER AS A NURSERY PEST. 27 



In the absence of Mr. Schoene, the following paper was read by Mr. 

 Parrott : 



THE WILLOW BORER AS A NURSERY PEST. 



(Cryptorhynchus lapathl L.) 

 By W. J. Schoene, Genera, A. Y. 



The willows and poplars along the streams and canals, ornamental 

 willows in the cities, and poplars and willows in the nursery are 

 being seriously injured by this beetle. The first noticeable out- 

 break of the insect in this State occurred in a nursery at Rochester 

 in 1902, and this species is iioav a serious pest in various parts of the 

 State. In many poplar and willow plantations the beetle has been 

 estimated to destroy 10 per cent of the stock and in some instances 

 the entire plantation has been ruined. The species of willow and 

 poplar that have been observed to sustain conspicuous injuries are: 

 Populus monilifera, Salix lucida, S. caprea, S. cordata^ < s '. sericea, 

 S. alba, and S. amygdaloides. 



This insect has been discussed in a comprehensive manner by 

 Prof. F. M. Webster in a paper entitled " The Imported Willow and 

 Poplar Curculio," which was presented before the Columbus Horti- 

 cultural Society. This treatise also contains some observations made 

 by Mr. A. H. Kirkland on the life history of the beetle and its de- 

 structiveness in Massachusetts. 



The increasing importance of this species to the nursery interests 

 of New York prompted an investigation to determine its life history 

 in this State for the purpose of ascertaining a practical method for 

 the control of the pest in poplar plantations. The aim of this paper 

 is to call attention to the results that have been attained. 



To understand clearly the trend of the work it is well at this time 

 to review in brief the life history of this insect. Oviposition com- 

 mences about August 1 and lasts through September. The eggs 

 hatch in eighteen to twenty-one days, and the larva upon hatching 

 begins to bore in the cambium layer, where it finds subsistence. As 

 it approaches maturity it makes a channel in the heartwood. The 

 larva 4 commence to pupate about July 1 and the beetles begin to 

 emerge two weeks later. For the next ten weeks the adults can be 

 found in abundance. Before beginning to deposit eggs the beetles 

 feed for a week or ten days on the bark of one-year shoots, after 

 which they are more often found upon the older parts o\' the tree. 

 especially in the injured portions of the bark and corky overgrowths 

 caused by pruning. It is because of the large number o( punctures 

 on the young wood that the work of the adult is especially noticeable. 

 This habit at once suggested the possibility o( using arsenical sprays 



