THE POPLAR AND WILLOW BORER 



(Cryptorhynchus lapathi Linnaeus) 



Order, Coleoptera Family, Curculionida 



ROBERT MATHESON 



Ever since its introduction from Europe, in 1882, the poplar and willow 

 borer or weevil has been a serious pest, not only in nurseries in the eastern 

 part of the United States but also to the basket willow industry and to. 

 poplar and willow trees used for landscape planting. During the past 

 ten to twenty years the weevil has become^so abundant in many eastern 

 nurseries that in many cases the nurserymen have almost abandoned 

 the raising of Carolina and other species of poplars to supply the demand 

 for a rapidly growing shade tree. Also many young groves of poplars 

 have been seriously injured, while large shade trees have been rendered 

 unsightly by the breaking off of branches that have been so riddled by the 

 boring of the larvae as to be unable to resist high winds. 



As this beetle is largely distributed through infested nursery stock, it 

 would seem that the most efficient means of reducing the injury that 

 it causes would be by controlling its work in the nurseries. If nursery- 

 men could furnish trees known to be absolutely free from the pest, its 

 further distribution would be restricted, and means could then be adopted 

 to control its activities where it is at present causing serious injury. Dur- 

 ing the past three seasons the writer has conducted experiments which 

 have proved very successful in controlling this pest under nursery con- 

 ditions. These experiments are discussed in the present bulletin, which 

 also gives a biological account of the insect. 



HISTORY OF THE SPECIES 



In Europe 



The poplar, willow, or alder snout beetle, the Erlenrussler of German 

 writers, is a European insect. For centuries it has been a pest to alders 

 and willows in Europe, and it has been the subject of many entomological 

 papers. 



Linne (1758) described the adult in his Sy sterna Natur&, giving as 

 its host plant Rumex lapathi. Curtis (1791) published the first account of 

 the natural history of the beetle. He found the larvae injuring ornamental 

 willows in his garden. He first observed the work of the beetle on Salix 

 riminalis in 1780, and after a few years of study succeeded in finding all 

 its stages except the egg, which he supposed was laid under the bark or 



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