PROTECTING PLANTS 201 
The white maggots that feed on the roots hatch from eggs laid 
near the plant at the surface of the ground by a small fly somewhat 
resembling the common house fly. Hollow out the earth slightly 
around every plant and freely apply carbolic acid emulsion diluted 
with 30 parts of water. Begin the treatment early, a day or two 
after the plants are up or the next day after they are set out. Repeat 
the application every 7 to 10 days until the latter part of May. It 
has also been found to be practicable to protect the plants by the use 
of tightly fitting cards cut from tarred paper. (See page 187.) 
Canker-worms. — These caterpillars are small measuring-worms or 
loopers that defoliate apple trees in May and June (Fig. 217). The 
female moths are wingless, and in late fall or early spring crawl up 
the trunks of the trees to lay their eggs on the branches. Spray thor- 
oughly once or twice, before the blossoms open, with 1 lb. Paris green 
or 4b. arsenate of lead in 100 gal. of water. Repeat the application 
after the blossoms fall. Prevent the ascent of the wingless females by 
means of sticky bands or wire-screen traps. 
Case-bearers on apple. — The small caterpillars live in pistol-shaped 
or cigar-shaped cases, about + in. long. They appear in spring on 
the opening buds at the same time as the bud-moth and may be con- 
trolled by the same means. 
Codlin-moth. —The codlin-moth lays the eggs that produce the 
pinkish caterpillar which causes a large proportion of wormy apples 
and pears. The minute eggs are laid on both the leaves and on 
the skin of the fruit. Most of the caterpillars enter the apple at the 
blossom end. When the petals fall, the calyx is open and this is the 
time to spray. The calyx soon closes and keeps the poison inside 
ready for the young caterpillar’s first meal. After the calyx has closed, 
it is too late to spray effectively. The caterpillars become full grown 
in July and August, leave the fruit, crawl down on the trunk, and there 
most of them spin cocoons under the loose bark. In most parts of the 
country there are two broods annually. Immediately after the blos- 
soms fall, spray with 1 Ib. Paris green or 4 lb. arsenate of lead in 100 
gal. of water. Repeat the application about 3 wk. later. Use burlap 
bands on trunks, killing all caterpillars under them every ten days 
from July 1 to August 1, and once later before winter. 
Cucurbit (cucumber, melon, and squash) insects. — Yellow, black- 
