the brown-tail moth in new hampshire. 217 



Remedies. 



Destroying the Winter Webs. 



Cutting' off and burning' the winter webs (as described 

 in Bulletin 122) is by far the most practical means of con- 

 trolling the pest. The efficiency of their destruction was 

 ^well shown in the City of Somersworth during the past sum- 

 mer. The city and private property owners had done most 

 excellent work the previous winter in destroying the webs, 

 but in one or two cases the ignorance or obturacy of the 

 property owner prevented the destruction of the webs by 

 the city employes. In one small yard with scarcely a dozen 

 fruit trees where the webs were not destroyed the caterpil- 

 lars appeared in such numbers that every apple tree was 

 absolutely defoliated (see figure 2) and were gathered by 

 the peck at the bases of the trees. Thorough spraying of 

 the trees with arsenicals and spraying the caterpillars which 

 had crawled on neighboring fences and houses with pure 

 kerosene, destroyed most of them. But the expense was ten 

 fold what it would have been to have pruned off the webs 

 in winter, and enough caterpillars escaped destruction to 

 reinfest the whole community. In another case a limb of 

 a large apple tree (Fig. 3, a) overhung a neighbor's yard 

 in such a way that it was difficult to remove the nests with- 

 out entering the adjoining property. Permission to do so 

 was refused. As a result this branch and another tree 

 (Fig. 3, c) on the untreated property was defoliated, while 

 the rest of the tree (Fig. S, b), from which the nests had 

 been removed, bore its normal foliage unmolested. 



Spraying. 



Frequently we are asked whether the caterpillars cannot 

 be controlled by spraying. Spraying is effective if done 

 early in May while the caterpillars are still young, but it is 

 so much more expensive than to destroy the winter webs 

 that it is rarely to be advised as the principle means of con- 

 trol of the brown-tail moth. When the eggs hatch in early 



