56 INSECTS AFFECTING VEGETATION 



"West. The twig-borer is principally an enemy of the peach, and 

 usually we hear of it in connection with its damage to this fruit. 

 It may be found, however, on all stone-fruit trees, but shows a de- 

 cided preference for the peach. The larvae, hibernate in the little 

 silk-lined chambers constructed within the bark and very close to its 

 surface. 



In the spring of the year, about the time the peach trees bloom, 

 the larvae leave their winter quarters and eat into the tips of the 

 twigs, either beginning their work at the extremities or a short dis- 

 tance below, sometimes hollowing them out for usually a distance 

 of less than an inch from where the twig was entered, leaving a 

 mere shell or hoilow cylinder of the portion in which they have fed. 

 Again they may merely gouge out the tip of a twig on one side, en- 

 tering in as far as the pith and then leaving for some other twig. 

 Thus they go from twig to twig, feeding first in one and then in an- 

 other, until often the tips of a great many branches will be killed 

 back, thereby checking their growth and more or less injuring the 

 tree. The detection of their work is no difficult matter a short time 

 after they begin feeding, for the leaves of affected twigs soon wilt, 

 and later dry up from the injury done to them. (Year Book 1905, 

 U. S. Dept. of Agr. ; Bui. 169, Col. Exp. Sta.) 



The twig-borer moth is a tiny, gray insect, about *4 inch in 

 length and having a wing expanse of about l /2 inch. It is quite a 

 beautiful little moth with its dark gray, fringed wings. It may be 

 said that arsenate of lead, applied in the spring at the time the buds 

 of the peach are beginning to open, will control the peach twig- 

 borer as effectively and cheaply as the lime and sulphur wash, up to 

 50 gals, of water when the buds show pink at tips. (Year Book 

 this time the most universally used. Use at the rate of 5 Ibs. to 

 1905 ; Col. E.S.B. 169.) 



The Brown Mite. This mite passes the winter almost entirely 

 in the egg stage. These eggs are tiny, red spherical-shaped, glassy 

 objects, usually deposited in or near crotches of the branches. Hatch- 

 ing takes place in the spring. At first the young mites are red in 

 color and have only six eggs. Upon feeding for a short time moult- 

 ing takes place, after which the mite is olive green, or brown in color, 

 and has eight legs more or less tinged with red. It feeds principally 

 upon the leaves, occasionally attacking the fruit, and may be detected 

 by the faded out, pallid appearance of the foliage, dotted here and 

 there with little black specks of excreta. Apple, peach, plum, cherry, 

 pear, and almond trees were found infested. Apricot and quince do 

 not seem to be troubled. Flowers of sulphur, one pound to three gal- 

 lons of water, and enough soap so that the sulphur -will mix with 

 water, is a perfectly effective remedy when used as a summer spray. 



The Red Spider. This mite differs from the preceding one in 

 its wintering habits; instead of living over in the egg stage, as the 

 brown mite does, this species hibernates in the soil as an adult, close 

 to trees upon which it has been feeding, or underneath rubbish of 

 any kind. Eggs are laid in the spring by mites that have lived 



