40 MAINE AGRICULTURAL EXPERIMENT STATION. 



about 3-16 of an inch in length, could fly off unharmed if the 

 tanglefoot is not placed in the upper rim of the barrel. It is 

 suggested that these barrels be placed in the vicinity of wood- 

 lots in which browntail nests are known to be present. 



Gathering and burning the eggmasses. — During the July flight 

 and the egg laying period the conspicuous brown egg masses 

 can be removed by picking the infested leaves and burning them. 

 No other treatment for very small trees would be necessary. 



Spraying. — In August when the newly hatched caterpillars 

 are young they can readily be killed as they are at this time 

 especially susceptible to the poison. Some years the browntail 

 caterpillars feed late into the fall, many becoming half grown 

 and working about the fruit as well as the leaves. This experi- 

 ence leads us to emphasize the need of an August spray for this 

 pest for while the species normally forms its winter nest while 

 tiny and before it has fed more than a few weeks this habit 

 has many exceptions and the late feeding on trees in fruit is a 

 serious menace on account of the poisonous hairs shed by the 

 caterpillars. It is less satisfactory to spray in the spring as 

 the caterpillars if numerous eat the tender leaves as fast as 

 they unfold. Then, too, the leaves are constantly expanding in 

 the spring, and fresh unpoisoned leaf surface is exposed soon 

 after a spray has been applied. Thus one August spray will do 

 what it would take several applications to accomplish in the 

 spring. The older caterpillars in the spring are less susceptible 

 to sprays. 



There is, however, no excuse for an orchardist having 

 brown-tail "caterpillars on his trees in the spring because even 

 if he neglects the August spray he has all winter in which to 

 gather the nests. 



Although there is nothing spectacular in collecting inactive 

 egg masses, August spraying, or gathering winter nests, we 

 should not lose sight of the fact that a single egg mass or a 

 single winter nest means from 150 to 350 moths on the wing 

 next July, and that one August spray in the fall for a tree 

 with 1000 egg masses, no uncommon occurrence in thickly 

 infested regions, prevents 300,000 moths more or less, taking 

 flight the next season. 



