DIVISION or 



FORESTRY 



COLLEGE Of A AGRICULTURE 

 UNIVERSITY OF CALIFORNIA 



THE FOREST TENT CATERPILLAR 



BY CLARENCE M. WEED 



DURING the last three years, in many 

 parts of New Hampshire and neigh- 

 boring states, there has been a serious 

 outbreak of the insect which has long 

 been known as the Forest Tent Cat- 

 erpillar, although in most regions 

 where it has recently been present it 

 is called the Forest Worm. It has 

 attacked forest, orchard, and shade 

 trees, and has done a great deal of 

 damage in many regions of New Eng- 

 land. 



This is no new pest : for a century 

 or more it has been known as a 

 destructive insect. At frequent in- 

 tervals in the past it has ravaged 



orchards and woodlands in widely separated states ; from Maine 

 to Texas severe attacks by it have been recorded. 



These Forest Tent Caterpillars hatch from eggs which are 

 deposited in cylindrical masses that form complete circles upon 

 the smaller twigs of a considerable variety of trees. The 

 appearance of these ''caterpillar belts" is shown in Fig 21 ; 

 the eggs are covered with a brittle substance which gives the 

 mass a shiny appearance, especially in a bright light. 



The young caterpillars or larvae come forth from the egg in 

 spring about the time the leaves of the trees begin to unfold. 

 When first hatched they are tiny creatures, scarcely one-tenth 

 of an inch long, showing under a lens that the blackish body is 

 provided with a covering of long brownish or grayish hairs. 



FIG. 2i. Egg Masses. 



