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NEBRASKA STATE HORTICULTURAL SOCIETY. 



ing these root lice is the use of scalding hot water freely poured 

 around the roots of the trees. If the trees are to remain in the soil, 

 the roots may be laid bare, and the water used nearly boiling without 

 injury; but where they have been taken up for the purpose of trans- 

 planting, and are to be dipped in the hot water, the temperature should 

 not exceed 150° Fahr.; under these circumstances, from 120° to 150° 

 would suffice for the purpose. A mulch placed around the trees for 

 some time previous to treatment has been found useful in bringing 

 the lice to the surface, where they can be more readily reached by the 

 hot water. Drenching the roots with soap-suds has also been recom- 

 mended, to be followed by a liberal dressing of ashes on the surface." 



THE APPLE-TREE APHIS. 

 (Aphis mali Fabr. ) 



Recently another plant 

 louse has been doing consid- 

 erable injury to the apple 

 trees of some portions of 

 eastern and southeastern Ne- 

 braska. This latter insect 

 is the one commonly known 

 as the Apple-tree Aphis. 

 It differs considerably from 

 the root louse of the apple 

 in several points, as will be seen by reference to figures 9 and 10, the 

 former representing a wingless and the latter a winged louse. As 

 will be seen in the figures, this louse of both forms is provided with 

 a pair of honey tubes, which issue from the upper surface of the ab- 

 domen near its apex. It also has the body destitute of any covering 

 like that found upon the root louse; and its antennae or feelers are as 

 long as its body, while the legs are also long and slender. In color 

 the Apple-tree Aphis is green or greenish yellow, the winged speci- 

 mens, as well as the apterous, being marked to some extent with black. 

 The presence of this louse in an orchard can be readily detected by 

 the curled appearance of the leaves which it infests. When the in- 

 sects attack a leaf it curls or twists around so as to shelter them from 

 rain, as well as to afford a partial protection against its natural ene- 

 mies. The life history of this plant louse is given briefly as follows 

 by the author already quoted : 



Fig. 9. — The Apple-tree Aphis (Aphis mali), winged 

 viviparous female. [Original, drawing by T. A. 

 Williams.] 



