The More Important Apple Insects. 85 
an inch in length. The male moth has dark gray forewings, which are crossed 
with three dark bands. On the back of the abdomen of both the male and female 
are several rows of reddish spines by which this species may be distinguished 
from the fall cankerworm. The eggs (fig. 61) are considerably less than one 
thirty-second of an inch in length, oval in shape, and yellowish green, some- 
times showing a purplish iridescence. The young larve hatch about the time 
the foliage of the apple commences to appear and immediately start feeding. 
The growth is completed by late spring, when the larve usually lower them- 
selves to the ground by means of a silken thread. The full-grown larva (fig. 
62) is slender, about an inch long, varying in color from yellowish brown to 
black. There are often three broken yellow stripes above the spiracles, a nar- 
row yellow stripe below the spiracles, and a broad greenish-yellow stripe along 
the lower surface, bordered on each side with black. ‘There are only two pairs 
of prolegs, which necessitates the larve looping as they crawl, after the manner 
of measuring worms. 
As already stated, orchards properly sprayed for the codling moth and leaf- 
eating insects are rarely if ever injured by cankerworms. Both the spring and 
fall cankerworms are controlled by 
thorough spraying of the trees with 
arsenate of lead at the usual strength, 
though if the caterpillars are half- 
grown or larger when the application 
is made, the quantity of arsenate of 
lead should be increased. Trees may 
also be protected by means of bands 
of sticky material or bands of cotton 
batting (see pp. 84-85) placed around 
the trunk a month or two previous to 
the time the buds usually begin to 
swell. These barriers will keep the 
females from crawling up the trees 
to deposit eggs and will, if properly 
applied, prevent the young larvze that may hatch below the bands from ascend- 
ing the trees. Thorough plowing and cultivation of the soil after the larvze have 
pupated in late spring will be effective in destroying many of the insects while 
in this helpless stage. 
Fic, 62.—Larve of the spring cankerworm. 
Enlarged. 
FALL CANKERWORM.” 
The caterpillars of the fall cankerworm, known also as loopers, measuring- 
worms, or spanworms, attack the foliage of the apple in the manner de- 
scribed for the spring cankerworm, and the two species, along with certain 
other loopers, may often be present on the trees at the same time. The fall 
cankerworm is a more general feeder than the spring form, attacking, in addition 
to the principal pome and stone fruits (fig. 63), the hackberry, common hickory, 
linden, walnut, butternut, etc. It cceurs generally over the northeastern United 
States and in Canada, extending westward to the Central States. It is also 
present in California, attacking various deciduous fruits. 
The life history of the present species differs somewhat from that of the spring 
cankerworm in that the winter is passed chiefly in the egg stage, the eggs being 
deposited usually in the fall, though some eggs are laid in the spring by moths 
that emerge at this time. The dark gray eggs, which are arranged neatly side 
23 Alsophila pometaria Harris. 
