5£ APPLE LEAVES, PLANT-LOUSE BLACKENS THE TREE. 



every crevice of the bark, in many places piled up and filling the? 

 cracks, and others were irregularly dropped among the lichens 

 and moss growing upon the bark — every unevenness of the sur- 

 face, or wherever a roughness afforded a support for them, being 

 stocked with as many as could be made to cling to it. The eggs 

 were then of a light yellow or green color, and were so slightly 

 glued in their places that it was evident by far the largest part of 

 them would be washed away by rains or brushed off by the driv- 

 ing snows of winter. But I by no means anticipated such a great 

 diminution in their numbers as actually occurred. I should judge 

 that in the spring several hundreds had disappeared for every one 

 that then remained. 



The present year (1855) the apple plant-louse, as well as species 

 infesting willows and some other trees, appears to be unusually 

 prolific, and has excited much alarm among many owners of young 

 orchards/for it is young thrifty-growing trees which are most in- 

 fested by it. In one instance a gentleman came to me a distance 

 of twenty-five miles, bringing specimens of this insect, to learn its 

 name and what measures he could resort to for destroying it, and 

 in the Country Gentleman of July 19, (vol. vi. p. 48,) is a letter 

 from William Gilchrist, of Hebron, Washington county,giving an 

 account of its depredations upon his trees, many of which were in 

 danger of perishing unless they were relieved from these vermin. 

 Norman Briggs, Esq., of Schaghticoke Point, informs me that par- 

 ticular varieties of the apple appear to be much more infested by 

 this insect than other varieties; thus the Sour Bough, wherever it 

 was growing in his grounds, was overrun with lice, whilst among 

 the, kinds least affected were the Northern Spy and Red Astrachan. 



As already stated, this insect locates itself upon the green suc- 

 culent shoots at the end of the twiggs, upon the under surface of 

 the leaves, and upon the leaf-stalks. The leaves being of a com- 

 paratively stiff, leathery texture, do not become w r rinkled and 

 plaited like those of the p^ach, the snowball, and many other 

 shrubs and trees; they, however, curve backwards, often to such 

 an extent that the point of the leaf touches the stalk on which it 

 grows, thus furnishing to the insect a comparatively secure covert 



