PROTECTING PLANTS 205 
Pear insects. — The psylla is one of the most serious insects affecting 
the pear tree. It is a minute, yellowish, flat-bodied, sucking insect 
often found in the axils of the leaves and fruit early intheseason. They 
develop into minute cicada-like jumping-lice. The young psyllas 
secrete a large quantity of honey-dew in which a peculiar black fungus 
grows, giving the bark a characteristic sooty appearance. There may 
be four broods annually and the trees are often seriously injured. 
After the blossoms fall, spray with kerosene emulsion, diluted with 6 
parts of water, or whale-oil soap, 1 lb. in 4 or 5 gal. of water. Repeat 
the application at intervals of 3 to 7 days until the insects are under 
control. Tobacco extracts may be tried. 
The pear slug is a small, slimy, dark green larva which skeletonizes 
the leaves in June, and a second brood appears in August. Spray 
thoroughly with 1 lb. Paris green, or 4 lb. arsenate of lead, in 100 gal. 
of water.’ 
Potato insects. — The Colorado potato beetle, or potato-bug, emerges 
from hibernation in the spring and lays masses of orange eggs on the 
under side of the leaves. The larvee are known as “slugs” and “‘soft- 
shells” and cause most of the injury to the vines. Spray with Paris 
green, 2 lb. in 100 gal. of water, or arsenite of soda combined with 
bordeaux mixture. It may sometimes be necessary to use a greater 
strength of the poison, particularly on the older ‘‘slugs.”’ 
The small black flea-beetles riddle the leaves with holes and cause 
the foliage to die. Bordeaux mixture as applied for potato blight 
protects the plants by making them repellent to the beetles. 
Raspberry, blackberry, and dewberry insects. — The greenish, spiny 
larvee of the saw-fly feed on the tender leaves in spring. Spray with 
Paris green or arsenate of lead, or apply hellebore. 
The cane-borer is a grub that burrows down through the canes, 
causing them to die. In laving her eggs, the adult beetle girdles the 
tip of the cane with a ring of punctures, causing it to wither and droop. 
In midsummer, cut off and destroy the drooping tips. 
Red spider. — Minute reddish mites on the under sides of leaves in 
greenbouses and sometimes out of doors in dry weather. Syringe off 
the plants with clear water two or three times a week, taking care not 
to drench the beds. Red spider and black mite may be treated with 
sulfocide. 
Rose Insects.— The green plant-lice usually. work on the buds, and 
