28 BULLETIN 250, U. S. DEPARTMENT OF AGRICULTURE. 
The results given below have been compared with the results with 
the same food plants growing in the open in so far as this data is 
available. 
SPRECKLED ALDER AND WILLOW. 
Lary fed on both species, but appeared to prefer alder in all stages. After 
the foliage on alder was nearly all eaten the larve attacked the willow. 
More adults were reared from these trays than from either alder or willow 
when fed alone. The larve grew steadily and attained large size. 
In the field both alder and willow, when growing together, are defoliated if 
the infestation is heavy. The alder is usually stripped first. 
AMERICAN BEECH AND CHESTNUT. 
Larve fed freely on the beech in the first two and last two stages. In the 
first stage there was no feeding on chestnut, and during the second stage the 
feeding was light, increasing to free in the third and fourth. After the fourth 
stage feeding decreased on chestnut. Preference for beech was noted except 
in third and fourth stages. 
Larve grew to medium size and a fair percentage reached the adult stage. 
AMERICAN BEECH AND RED OAK. 
Both of these foods were eaten freely throughout the experiment. Oak was 
a decided favorite in the first five stages. In the sixth stage feeding decreased, 
as the larve preferred the more tender leaves of the beech. The larve grew 
rapidly and were of large size. A good percentage reached the adult stage. 
In the field the larvze fed on the beech in the first two stages, then changed to 
the oak, where they fed until the last stage, when they returned to the beech. 
AMERICAN BEECH AND SUGAR MAPLE. 
Both these food plants were fed upon freely until the fifth stage, then mod- 
erately. A slight but continued decrease was noted on maple from the begin- 
ning of the fifth stage to the closing of the trays. Very little preference was 
observed in the first four stages. 
A few larve reached the adult stage. 
BLacK BIRCH AND WITCH HAZEL. 
There was no feeding on the birch during the first stage and but very little 
in the second and third. In the fourth and fifth stages the larve preferred the 
birch. The larve fed freely on witch hazel in the early stages. The cater- 
pillars were small and reproduction resulted from this experiment. 
GRAY BIRCH AND CHESTNUT. 
There was no feeding on the chestnut during the first stage, but a steady 
increase was noted thereafter. Feeding was constant on the gray birch in all 
stages. 
The larye grew slowly and were of small size and but few reached the adult 
stage. 
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