NOCTUA PINIPERDA. 821 



Pupa somewhat elongate, of a bright brown colour, with two 

 spines on its tail. 



b. Life-history. 



The moth appears from the end of March to the beginning 

 of May. 



The ? lays 30 to 70 round, dull-green eggs on the needles of 

 old Scots pines. 



The caterpillars hatch out in May, spin freely when young, 

 and are fully grown by the middle of July. 



Pupation takes place at the end of July or beginning of 

 August, under moss, dead leaves, on or in loose earth, usually 

 under the cover of the tree on which the insect feeds. The 

 pupae are sometimes found in colonies, in the holes whence 

 stumps, etc., have been extracted. 



Generation annual. The caterpillar sometimes appears in 

 enormous numbers, but is susceptible to changes of the 

 weather. It is tolerably common in pine woods throughout 

 Great Britain. 



c. Relations to the Forest. 



The caterpillar attacks chiefly the Scots pine, especially 

 when 20 to 40 years old, but in case of necessity it may feed 

 on older trees and other conifers, such as spruce, Weymouth 

 pine and juniper. 



When young the caterpillar, according to Eatzeburg, bores 

 into the bud-sheaths of the spring shoots, which thus become 

 brown, wilt and die. Later on the needles are attacked, 

 beginning with their edges, and finally they are entirely 

 devoured, usually on the lower branches, but also high up in 

 the crown. The attack lasts from May till July, but is not so 

 destructive as that of Gastropacha pini, L., as the Scots pines, 

 even if extensively stripped by it, usually form new buds and 

 recover. One should therefore await results before felling 

 woods that have been completely stripped of needles. Only 

 when the fatal rosettes of needles (Fig. 143) appear is the 

 death of the trees imminent. The insect inhabits hilly 

 regions, and is most common in forests where the soil has 

 become impoverished by removal of litter. 



