OIPSV MOTH AXD BROWX-TAII. MOTH. 



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Thaxter in 1888. Like all diseases of this nature, the benefit derived 

 from it is regulated largely by favorable or unfavorable weather 

 conditions. This fungus sometimes works to a slight degree on the 

 small caterpillars in the fall, and in some instances it is found in the 

 winter webs. As a rule, however, the greatest mortality of cater- 

 pillars takes place in the spring, when they are nearly full-grown, 

 and the pupae of the moth, under the most favorable conditions, 



FIG. 6. Red oak trees stripped by brown-tail moth caterpillars. Note old winter webs at tops of trees. 



