34 CIRCULAR 639, U. S. DEPARTMENT OF AGRICULTURE 
resting stage usually requires about 12 days in hot weather, but the 
period may be prolonged in the spring and winter months. 
At the end of the pupal stage the adult, or moth (fig. 39), emerges 
and the life cycle is complete. There appear to be five or six genera- 
tions a year in this locality which so overlap that it 1s impossible to 
tell them apart. 
CONTROL MEASURES 
CULTURAL PRACTICES 
It has been observed for many 
years in this region that cut- 
worms are most numerous on 
land that has been covered pre- 
viously with green vegetation 
such as pasturage, rye, oats, or 
other cover crop. This vegeta- 
tion apparently attracts the 
moths during the period of egg 
laying and afterward serves as 
food for the worms. Plowing 
under all vegetation a short time 
before setting tobacco does not 
rid the land of cutworms, as several species can develop on dead vege- 
tation, while other forms can survive for several weeks without food. 
If, however, the land has been 
kept cleanly cultivated for a pe- 
riod of at least 60 days before 
setting the tobacco plants, little 
trouble from cutworms is usu- 
ally experienced. During this 
interval there is no vegetation 
to attract the moths for egg lay- 
ing and the cutworms already 
in the soil continue their devel- 
opment, so that by the time to- 
bacco is set out the great major- 
ity of the cutworms shave passed 
into the harmless pupal stage. 
While the practice of keeping 
land free of green vegetation 
during the winter and spring 
months will reduce the number 
of cutworms in tobacco fields, Al Bb 
this recommendation should not ae ee ae ee a 
be followed if it conflicts DEF worm: A, Doreail vicue acuta 
riously with a fertility or dis- x ge 
ease-control program. 
FicurE 37.—Mature larvae of the gran- 
ulate cutworm, about natural size. 
THE USE OF POISONED BAIT 
The number of cutworms in the soil may be er eatly reduced by the 
use of poisoned bait. The following bait formula is recommended : 
Pounds 
Wheat bran_ parecer ae ar isp SS eee ee PTT 2 8 pl 50 
Paris green ane. eee |. mee Pet il 
Water to moisten. 
