156 Control of Parasites 



also colored and ha\'e well-de\'eloped legs, usually live on 

 the leaves; the pupa generally and sometimes also the beetle 

 wintering either underground or in the litter. The different 

 species are more or less dependent on certain species of 

 trees; willows, poplars, elms, also oaks and pines having 

 their special pests. Here belong also the potato-beetle, 

 the asparagus-beetle, and the cucumber-beetle. The most 

 common and most destructive to ornamental trees is the 

 im])orted — 



Elm-leaf Beetle, the beetle being yellowish brown to green- 

 ish yellow with two or more black stripes on the wings, and 

 the half-inch larva yellowish black with black spots and 

 tufts of hair and wide yellow lines along the back and sides. 

 The foliage is characteristically eaten, the soft tissue between 

 the ribs being attacked in patches; the beetles eating irreg- 

 ular holes, the grubs systematically skeletonizing. The 

 grubs work on the under side of leaves from May until 

 August, together with the one to three or four broods of 

 beetles, which lay their yellow bottle-shaped egg clusters on 

 the under side of leaves. The pupa winters under the 

 fallen leaves near the base of the tree, and the beetle in all 

 sorts of sheltered places; they attack the leaves in spring 

 (April or early May) as soon as these are fully dex'eloped, 

 beginning at the top of the tree. 



The many broods, the prolific reproduction, and the fact 

 that both beetle and larva feed on the foliage, make this 

 pest most injurious, since in one season it may destroy two 

 or three sets of new foliage and exhaust the tree. 



Besides destroying the wintering beetles or pupae, either 

 mechanically or by hot water or kerosene, etc., spray with 

 arsenites as soon as beetles begin feeding, a second spray- 

 ing being applied when eggs begin to hatch or ten days 

 later. Since the beetles are disinclined to fly, a single tree 



