34 
BULLETIX 1476, tVS. DEPARTMENT OF AGRICULTURE 
CHARACTER OF INJURY TO PLANTS OTHER THAN CORN 
Injury to plants other than corn is of the same general character 
as that inflicted on corn, except that in some instances special parts 
of the plants appear to be habitually preferred as food or as shelter. 
(See Table 1.) 
Although some of the infestation in plants other than corn results 
from the larvae which haye migrated from susceptible plants grow- 
ing in the vicinity, such as corn or weeds, the eggs are commonly 
deposited upon a variety of vegetables, field crops, flowering plants, 
and weeds. Many of the resulting larvae feed and complete their 
development therein, particularly in the two-generation area of Xew 
England. 
VEGETABLES 
In addition to sweet corn, the most important vegetable hosts of 
P. nubilalsis (Table 2) are rhubarb, beets, mangels (fig. 16), celery, 
beans, spinach, peppers, tomatoes, potatoes (fig. 17). and Swiss 
chard. A summary of the more important obseryations relating to 
the character of injury to these plants is included in Table 2. 
With the exception of beans, which were slightly infested in the 
experimental plat at Silver Creek, X. Y., all of these obseryations 
are limited to the Xew England area. 
Table 2. — Character of injury to vegetables by Pyrausta nulilalis larvae 
(Xew England, 1913 to 1922) 
Xame of 
plant 
Parts of plant attacked ' ApP<?ara ^ infeSted 
Remarks 
Rhubarb. 
Beets. 
Celery. 
Beans. 
Spinach. 
Pepper. 
Tomato. 
Potato.. 
Leaf stalks, seed stalks, 
and main veins of 
leaves. Eggs depos- 
ited freely on leaves. 
Small larvae feed 
thereon. 
Leaf stalks, main veins 
of leaves. Rarely the 
fleshy portion of root. 
Eggs deposited freely 
on leaves. Small lar- 
vae feed thereon. 
Leaf stalks, main veins 
of leaves. Usually 
outer leaf stalks pre- 
ferred, although fre- 
quent injury to heart 
of plant. Eggs de- 
posited on leaves. 
Principally stalks, oc- 
casionally green beans 
and pods. Eggs le- 
posited on leaves. 
Leaves fed upon by 
newly hatched larvae. 
Leafstalks rarely tun- 
neled. Eggs deposit- 
ed on leaves. 
Stalks and fruit 
Swiss chard. 
Stalks, and rarely the ! 
fruit. 
Stalks. Eggs freely de- 
posited on leaves. | 
Small larvae feed 
thereon. 
Leaf stalks. Eggs oc- 
casionally deposited 
on leaves. Small lar- i 
vae feed thereon. 
Masses of dark-yellow 
frass, mixed with gum- 
like substance, exude 
from larval tunnels. Af- 
fected parts break over 
when injury is severe. 
Black, granular frass eject- 
ed from larval tunnels. 
Affected parts break 
over when injury is se- 
vere. 
Wet, discolored frass eject- 
ed from larval tunnels. 
Unless badly infested 
the injured leaf stalk 
does not break over. 
Masses of light-yellow 
frass extrude from larval 
tunnels. Affected parts 
break over when injury 
is severe. 
Light-yellow frass ejected 
from larval tunnels. In- 
jury very inconspicu- 
ous. 
Light-yellow frass ejected 
from larval tunnels. In- 
fested stalks break over. 
Seeds and pulp of fruit 
eaten. 
do 
Same as above. Tubers 
not infested. 
Black masses of frass eject- 
ed from larval tunnels. 
Usually the tunnel is 
discernible from surface 
of leaf stalk. 
Most susceptible of vegetable 
crops. Much of the severe in- 
jury occurs after close of com- 
mercial season. Plant not seri- 
ously affected by this injury. 
Plants very susceptible. Injury 
to leaves or leaf stalks does not 
seriously affect plant. Injury to 
beet root renders it unsuitable 
for food. 
Plants very susceptible. Injury 
to leaf stalk renders it unfit for 
food. Usually the injured por- 
tion may be removed and re- 
mainder of plant used. 
Both low bush and pole beans at- 
tacked.- Usually the severe in- 
jury occurs after beans have 
reached harvesting stage. X" um- 
ber of infested pods usually less 
than 1 per cent of total in field. 
Infestation by eggs or larvae usual- 
ly limited to less than 1 per cent 
of plants in field. Growth of 
plant not affected. 
Both sweet and hot varieties are at- 
tacked. Formation of fruit af- 
fected when stalks are attacked 
early. External signs of infested 
fruit not conspicuous. 
Do. 
Even severe breaking over of 
stalks does not appreciably af- 
fect formation of tubers. 
Growth of plant not appreciably 
affected. Injured parts unsuit- 
able for food. Usually the af- 
fected parts do not break over. 
