134 NEW YORK STATE MUSEUM 



give a whitish color to portions of the plant and rendered walk- 

 ing through the field extremely disagreeable. 



Chaitophorus aceris. The Norway maple has enjoyed up to 

 recent years comparative immunity from insect pests, and it was 

 therefore a serious disappointment to its admirers when this 

 species of plant louse injured it so seriously in the last two or 

 three years. The damage by this species has gradually increased, 

 and whereas in 1900 or thereabouts many of the trees had their 

 foliage somewhat disfigured by the sooty fungus growing in the 

 honeydew and drops of this sticky substance occasionally fell on 

 passersby or moistened the sidewalk beneath, in 1903 some of 

 these unfortunate trees had their foliage almost ruined by this 

 pest. Many of the leaves were so badly curled that they pre- 

 sented only about one fourth of the usual surface, and this maple 

 instead of being an object of beauty, was a monument of misery 

 and an eyesore on the landscape. This was true not only about 

 Albany but in various sections of the State. This plant louse 

 can be controlled by thoroughly spraying with a contact insecti- 

 cide, such as whale oil soap, taking special pains to hit the insects 

 on the undersurface of the leaves, and it looks as though some 

 such treatment would have to be adopted in coming years if we 

 are to keep this shade tree in good condition. This species was 

 the cause of more complaint and incidentally gave more employ- 

 ment to parties operating a spra;ying outfit in Troy, than even 

 the notorious elm leaf beetle (Galerucella luteola 

 Mull.). 



Elm aphis (Callipterus ulmifolii Mon.) . This deli- 

 cate species occurs somewhat generally on our American elms, 

 and occasionally becomes ^exceedingly injurious, as was demon- 

 strated in 1897 and again in 1903. This little plant louse was 

 so abundant on many trees during the past summer that the 

 foliage became badly smeared by the honeydew, lost its color and 

 all but failed to perform its proper functions. This condition 

 was somewhat general in the vicinity of Albany, at Palatine 

 Bridge in the Mohawk valley, and a similar state of affairs was 

 reported from Ogdensburg, St Lawrence co. The most of the 



