38 
BULLETIN 1476, U. S. DEPARTMENT OF AGRICULTURE 
Table 3. — Character of injury to field crops by Pyrausta niibilalis larvae 
(New England, 1919 to 1922) 
Name of 
plant 
Parts of plant attacked 
Appearance of infested 
plants 
Remarks 
Millet. 
Hemp.. 
Grain sor- 
ghums. 
Broomcorn. 
Barley. 
Cotton. 
Cowpea. 
Sorgo. 
Hop 
Buckwheat. 
Oats 
Johnson grass. 
Sudan grass. _ 
Soy bean 
Rape 
Sweet clover 
(white). 
Timothy 
Tobacco. 
Stems (culms) . Eggs 
rarely deposited on 
leaves. 
Stalks, seed heads. Eggs 
freely deposited on 
leaves. Small larvae 
feed thereon. 
do 
.do. 
Masses of light-yellow 
frass extrude from larval 
tunnels. Infested stems 
usually break over. 
Same as above. Plants 
break over only when 
severely injured. 
Red frass ejected from 
larval tunnels. Stalk 
breaks over just below 
seed head when severely 
injured. Resembles in- 
jury to tassel stem of 
corn. 
do 
Stems (culms). 
Stalks, bolls. Eggs freely 
deposited on leaves. 
Small larvae feed 
thereon. 
Stalks, pods. Eggs oc- 
casionally deposited 
on leaves. 
Stalks, seed heads. Eggs 
freely deposited on 
leaves. Small larvae 
feed on leaves. 
Vine (stem) and leaf 
stems. 
Stems 
Stems (culms). Eggs 
rarely deposited on 
leaves. 
....do 
Masses of light-yellow 
frass ejected from larval 
tunnels. Infested stems 
usually break over. 
Same as above. Bolls en- 
tered at base, under 
bracts, when nearly full 
grown. Dark -brown 
frass extrudes from en- 
trance holes. Larvae 
tunnel through carpel, 
iint, and seed. 
Masses of light-yellow frass 
extrude from larval tun- 
nels. Infested stems 
usually break over. In- 
jury to pods similar to 
beans. 
Appearance of injury sim- 
ilar to corn. Plants 
break over only when 
severely injured. Frass 
red in color. 
Light-yellow frass ejected 
from larval tunnels. 
Masses of white frass ex- 
trude from larval tun- 
nels. Infested stems 
usually break over. 
....do 
_do. 
....do 
Stalks. Feeding injury 
to leaves. Eggs found 
on leaves. 
Leafstalks. 
Stems 
do. 
Masses of light-yellow frass 
extrude from larval tun- 
nels. Plants break over 
when severely injured. 
Stems, seed heads. 
Stalks 
.do. 
Masses of dark brown frass 
extrude from larval tun- 
nels. 
Japanese millet very susceptible. 
European millet to a lesser ex- 
tent. Hungarian millet rarely 
attacked. 
Very susceptible. Found occas- 
ionally growing wild in Massa- 
chusetts area. Invariably in- 
fested when exposed to attack. 
Includes hegari, feterita, milo, and 
kafir. Hegari most susceptible 
and more severely injured than 
the others of this group. 
Appears to be able to withstand 
severe infestation without ap- 
preciable injury to the brush 
used in broom making. 
Formation of grain seriously af- 
fected when stem is attacked 
early in its development. Late 
attack not seriously injurious. 
Quite susceptible. Development 
of bolls prevented when stalk 
breaks over early in its develop- 
ment. Bolls not affected by 
slight or late injury to stalk. 
Plants killed by frost before 
bolls opened. 
Most of injury occurs late in the 
season. Growth of plant or 
yield of seed not appreciably 
affected. 
Except when severely injured the 
growth of plants infested is not 
seriously affected. 
Only occasionally infested. 1 
Grains reduced in size or their 
formation prevented entirely 
when injury occurs before seed 
head develops. 
Do. 
Yield of fodder or seed not ap- 
preciably affected. 
Do. 
Plants infested late in the season. 
Growth of infested plants not 
appreciably affected. Soybeans 
infested under field conditions in 
New York. 
Very slightly susceptible. No ap- 
preciable effect on plant. 
Same as above. White sweet 
clover grows wild in waste areas, 
in vicinity of Boston, Mass. 
Infested usually by smaller larvae. 
Full-grown larvae found rarely 
in larger stems. 
Infestation occurs during late 
season. No appreciable effect 
on plant. Larvae found in 
tobacco were dead, or died sub- 
sequently. 
1 Japanese hop (Humulus iaponkus) is grown as an ornamental in Massachusetts and under these condi- 
tions it is frequently and severely infested. 
