286 PROTECTION AGAINST INSECTS. 



Elytra regularly punctate- striate. Larvae vary in colour, 

 often nearly black above, with an olive-green middle line, 



yellowish below. 



b. Life-history, etc. 



The beetles come out in the spring from their sheltering 

 places, and lay their eggs on the under-surface of leaves of 

 willows Salix viminalis, L., S. purpurea, rubra, etc., and also 

 on poplars. The images and larvae attack the young shoots 

 and leaves, commencing with the under-surface, and eating 

 their way through the leaf, or up to its epidermis. 



Pupation takes place in the soil. The beetle lives through 

 the winter, hibernating in various localities ; it is found some- 

 times high up on willows in sheltered places, under the rough 

 bark of old pollards, in hollow stems of herbaceous plants, 

 among the terminal shoots of neighbouring young pine trees, 

 or on the soil amongst fallen leaves and old stumps of osiers. 

 They will also hibernate in the heaped-up peel of osiers, 

 which should not, therefore, be left lying about. 



Generation generally single, rarely double. This beetle is 

 extremely common and decidedly inj urious. In 1884, according 

 to Miss Ormerod, in osier beds in the Lymm district, near the 

 borders of Lancashire and Cheshire, it was estimated that 

 the whole crop of osiers on 50 atsres would have been destroyed 

 if protective measures had not been taken. 



c Protective Rules. 



i. Dragging across the osier-beds a rope weighted in the 

 middle. This operation, which should be repeated several 

 times, knocks off the beetles, which will lay their eggs on the 

 ground, where they die. 



ii. Sprinkling the osier-shoots with a strong solution of 

 wood ashes, or with Paris green (arsenite of copper, see 

 page 177). 



iii. Knocking the beetles off the osiers into square tin vessels 

 containing ashes, but this procedure must be done repeatedly. 



iv. Collection of the beetles in their winter quarters. 



Traps of birch-bark, planks, etc., may be put above the 

 flood-level ; under these the beetles collect in myriads for 

 shelter, and may then be destroyed. 



