32 SOME INSECTS INJURIOUS TO TRUCK CROPS. 
SUMMARY OF HABITS. 
From present knowledge of the caterpillar two generations annually 
are indicated, although only one has been observed. Moths have been 
reared by the writer in July and August and they have been captured 
out of doors during the same months and in September. From 
available data it would appear that an average life history would be 
about as follows : Egg period, 3 to 5 days ; first larval instar, 3 days ; 
second larval instar, 2 days; third, 5 days; fourth, 4 days; fifth, 
8 days, and pupal stage, 7 to 10 months. Hibernation occurs in the 
pupal stage. 
The observed food plants include asparagus, cabbage, collards, 
turnip, ruta-baga, rape, peas and related plants, greenhouse violet, 
tobacco, grass, and blackberry. Of wild plants, golden-rod and 
milkweed have been observed, the larva attacking the flowers of 
the former and the seed pods of the latter. 
METHODS OF CONTROL. 
Although the early habits of this species as it occurs in the field 
have not been observed, there is no doubt that, like the zebra cater- 
pillar, the young when first hatched are gregarious for some time, 
and hence may* be easily discovered and destroyed by mechanical 
means or by arsenicals. All of the caterpillars of this class readily 
succumb to arsenical poisons, and for this species in its occurrence on 
asparagus and some other plants arsenate of lead is to be preferred. 
It may be used at the rate of about 1 pound combined with 15 to 25 
gallons of water or Bordeaux mixture. If an adhesive resin soap, 
such as resin fish-oil soap, is added, it makes this mixture all the 
more permanent, and a single application is then all that is necessary. 
Paris green may be used in the same manner at the rate of 1 pound 
to 100 or 150 gallons of water. It is evident that this species, like 
the zebra caterpillar, does no particular harm as a rule in its first 
generation, but is much more abundant in the second or late fall gen- 
eration, when certain plants are injured by it. Owing to the diffi- 
culty of locating the larger larvae, it is evident that hand-picking 
would not be applicable for them in their later stages. 
