164 Control of Parasites 
large caterpillars or bringing them down by a stream of 
water, or cutting off the infested branches while the cater- 
pillars are still young and closely gregarious. 
Army-worms or Cui-worms comprise a number of species, 
some of which spin cocoons, others do not. They are typ- 
ical, medium-sized, night-moths; the usually hairless cater- 
pillars are also frequently night-prowlers. While mostly 
non-gregarious, some of them develop in such large masses, 
wandering over the ground, that the first name is applied 
to them, while the habit of cutting off buds and leaf parts 
leads to the second name. Some of the caterpillars are 
borers; others live underground, feeding on roots; the 
majority, however, live on the foliage of the host plant. 
The true Army-worm, a brownish, white-striped caterpillar, 
from one and a half to two inches in length, with a brownish 
moth, making two or three generations in the year, more 
frequently damages grass crops than trees. The velvety 
black, yellow-lined, hairy caterpillar of the Erratic Army- 
worm, the mottled gray worms of another cut-worm, as well 
as many others, climb the oak, elm, cherry, etc., by night, 
revealing their presence by the cut-off buds and leaf par- 
ticles which fall to the ground. Both deciduous and co- 
niferous trees find enemies in this group. Most of the moths 
of this group fly in summer and fall, usually wintering under- 
ground as caterpillars or pupe. 
The climbing cut-worms, which winter as such under- 
ground, can be prevented from climbing the trees by various 
bands. They can also be baited with poisoned bran (one 
ounce of Paris Green to three ounces of bran), placed at the 
base of the tree. If whole areas are infested, in addition 
to banding the trees, ditching and collecting in the ditches 
is recommended. 
INCH-WORMS or CANKER-WORMS (Geometrids), also called 
