468 CALIFORNIA FRUITS: HOW TO GROW THEM 



cobweb-like material, under which they take shelter in large colonies; 

 but one, at least, of the group does not spin a web, though it lives 

 in clusters on the tree. The worms can be killed by cutting off and 

 burning the twig holding the cluster or by burning the colonies in 

 place with a torch on the end of a pole, or by spraying the foliage 

 with lead arsenate or Paris green. The pest can be reduced while 

 pruning by carefully collecting and burning the egg clusters, which 

 encircle the twig. 



Red-Humped Caterpillar. Striped caterpillars, not hairy, but 

 having two rows of black spines along the back, also living in clusters ; 

 of reddish color with yellow and white lines; a short distance back 

 of the red head of the caterpillar is a red hump on which are four 

 black spines ; black spines are also scattered over the body, but smaller 

 than those on the back. Spray with lead arsenate or Paris green, or 

 cut off and burn colonies. 



Caterpillar of Tussock Moth. A conspicuous caterpillar with 

 four short, brush-like tufts on its back, and two long, black plumes 

 at the front, and one at the rear of the body. This leaf-eater is found 

 on apple, pear, plum and sometimes on other fruit trees, also on the 

 walnut and oak. The caterpillars are peculiarly resistant to arsenical 

 sprays and can not be successfully controlled by these. The larva 

 spins a cocoon sometimes in the fold of a leaf, more commonly in 

 crotches or rough places on the bark, or even on adjacent buildings 

 Or fences, and the female, after emerging from the cocoon, deposits 

 her eggs upon the outside of it. The insect is fortunately very freely 

 parasitized in the egg form and prevented from wide injury. It can 

 be controlled by destroying the egg masses during pruning, as they 

 are white and very conspicuous. 



Pear and Cherry Slug. A small, slimy, dark-colored worm, with 

 the fore part of the body notably larger than the rear part, eating 

 the upper surface of the leaves but not usually making holes through 

 them. The insect can be checked by throwing fine road dust or air- 

 slacked lime over the tree, which cakes upon the slime of the worm 

 and destroys it. On a large scale an arsenate of lead or Paris green 

 spray is best. 



Saw-Fly Worm. There are several larvae of saw-flies which 

 do much injury to pear trees, currants, etc., by eating the whole leaf 

 substance except the larger ribs. The worms are small, not slimy like 

 the pear slug, the one infesting the pear being about half an inch 

 when fully grown. Its general appearance and work are shown by 

 the engravings. The most available remedy is an arsenate of lead 

 or Paris green spray. 



Large Caterpillars on Grape-vines The grape-vine is often 

 seriously injured by the attacks of very large leaf-eating worms two 

 inches and upwards in length, sometimes with a large horn, or spine, 

 sometimes without. They are larvae of several species of Sphinx 

 moths or hawk-moths. The worms when new hatched can be killed 

 by an arsenical spray or by hand-picking. The numbers of worms 

 can be reduced by killing the large moths which are abundant at 



