THE LARGE LARCH SAWFLY. 45 
the caterpillars of VV. Zrichsoni have been at work in very large 
numbers over a considerable area in Cumberland. The trees 
cover the mountain up to an elevation of 1600 feet. Part of 
the area is made up of pure larch, which suffered more than 
another portion of the wood where the larch is mixed with oak 
and a few other broad-leaved species. The attack was first 
observed in 1904; it was more serious with the spread of the 
insect in 1905; and again in the summer just past great havoc 
was done. Caterpillars were sent to the Board of Agriculture 
and Fisheries for determination and report in August of this 
year, and a visit to the affected district followed. 
The worst infested area, known as Dodd Wood, is on Miss 
Spedding’s Merehouse Estate, and is situated about four miles 
from Keswick, in the Bassenthwaite direction. In shape the 
Dodd Wood is somewhat conical, hence is exposed to all points 
of the compass; the largest part, however, faces south. The 
age of the trees attacked varies from twenty years to seventy 
years and over, and the fact of tall trees being attacked adds 
greatly to the difficulty of satisfactorily combating the cater- 
pillars and the adult sawflies. When I visited the place in the 
last week of August, the brown and withered appearance of 
many of the trees attested the severity of the infestation. At 
some hundreds of yards distance, looking up at the wood, the 
eye could easily pick out the defoliated trees. Some of them 
were practically in their winter condition, devoid of leaves. 
Others which had been defoliated in July had by mid-August 
started to produce new leaves, so that on inspection at the end 
of August such larches looked as they normally do in April or 
May, with the dwarf shoots bearing tufts or clusters of partly 
grown leaves. 
Some seventy-year-old larches felled at the end of July and 
the beginning of August had thousands of the sawfly caterpillars 
on them. These caterpillars, many of them dislodged by the 
fall of the tree, made their way to the trees standing near and 
attempted to ascend them, the bases of the trunks of several 
hawthorns, for example, being hidden by their numbers. The 
caterpillars, numerous and easy to find on the trees up to the 
third week of August, were by the fourth week, in the great 
majority of cases, full fed, and had left the trees and made their 
way into the moss and litter on the ground below, in order to 
make their cocoons. Here and there in such places, on looking 
