14 
BULLETIN 922, U. S. DEPARTMENT OF AGRICULTURE. 
from the middle to the end of June do not stop feeding until early in 
July. The amount of foliage eaten during the postdormant period, 
that is, after the summer inactive period, is 1.48 square inches and 
extends over *an average of 82 days, that is, not one-tenth as much 
per day as is eaten in the predormant stage (Table VI and fig. 9). 
The amount of food consumed by the individual beetle during its 
entire adult stage averages 4.76 square inches, 0.045 erf an inch per 
day during the feeding periods. The feeding by the beetles is there- 
fore so slow and gradual that they seldom do an appreciable amount 
of injury except when in unusual numbers. On the other hand, the 
larva needs approximately 2 square inches less of foliage for its 
development than is eaten by the adult, but of the 3.09 square inches 
of leaf eaten by each larva, 2.48 inches are consumed during the last 
instar, which occupies a period of 10 days or less, and the large amount 
of foliage taken in so short a period greatly increases the liability of 
injury. 
. 
MAY JIM J JULY 
1 1 1 
AUGUST 
SEPTEMBErJoCTOB ER NOVEMBER 
DECEMBER 
Fig. 9.— Diagram showing the comparative amounts of clover foliage 
eaten by adult beetles of the clover-leaf weevil dining the different 
months of the season. 1 
Tables IV, V, and VI give the amounts of clover foliage eaten by 
adults and larvae. 
Table IV. — Average amounts of clover foliage eaten by adult and larva of Hypera punctata. 
Stage. 
Average 
amount 
food 
eaten. 
Average 
length 
feeding 
period. 
Average 
per day. 
Inches. 
3.28 
i .74 
.019 
.084 
.504 
2.480 
3.087 
4.02 
Days. 
23.5 
82.0 
18.6 
10.0 
8.5 
14.0 
51.1 
105.5 
0.139 
.009 
.001 
.008 
.059 
.177 
.06 
.038 
1 The beetle consumes at least an equal amount of stem during this period and this could not be measured. 
1 As recorded in Table IV, at least an equal amount of stem is eaten in the fall in addition to the foliage, 
and due consideration is taken of this fact. 
