174 Pecan-Growing 



FALL WEBWORM 



The fall webworm becomes very conspicuous by its webs in 

 pecan trees in the late summer and early fall. The colony of 

 larvae constructs a web covering a cluster of leaves on which 

 they feed. This web is extended to other leaves as those 

 within are eaten. The caterpillars leave the web in late 

 autumn and pupate in loosely constructed hairy cocoons be- 

 neath scales of bark on the trunk or under rubbish on the 

 ground. The adult moths emerge in April or May and lay 

 their eggs in clusters on the leaves of the pecan tree. These 

 eggs hatch about a week later, and each group of larvae form 

 a web in which they feed. These larvse pupate, and the 

 second brood of moths are out by the middle of the summer. 

 From the eggs of these moths hatch out the larvge which are 

 so conspicuous, by their webs, in pecan trees during the fall. 



Control. 



Webs of the first generation of larvae may be destroyed 

 by burning them out w^th a torch fixed on the end of 

 a long pole, or twisted out of the trees by means of a long 

 slender pole with a nail driven through one end. If this work 

 is done thoroughly, the number of larvse in the second genera- 

 tion will be small. 



When there is a heavy infestation of the fall webworm, 

 the trees may be sprayed with arsenate of lead, using the 

 same mixture as is recommended for the leaf case-bearer. 



PECAN OR WALNUT CATERPILLAR 



(Datana integerrima, G. & R.) 

 The egg-laying habits of the adult of the pecan or walnut 

 caterpillar are very similar to those of the fall webworm. 



