554 MISC. PUBLICATION 657, U. S. DEPT. OF AGRICULTURE 
rent year’s growth is fully developed, and spin their cocoons in the 
duff near the base of their host tree. 
The full-grown larva of Neodiprion sertifer (Geoff.) is about 7% 
mch in length. The head is black and the body is dirty be ish green 
with a longitudinal dor- 
sal of lighter shade. Lat- 
erally there are two whit- 
ish lines bordering a 
stripe of very intense 
green or sometimes black- 
ish, which has a tendency 
to break up into spots. 
The thoracic legs and 
back of the anal segment 
are black (fig. 146, D). 
Arising from the dorsal 
and pleural areas of the 
body are many short 
black setae, those on the 
dorsum being arranged 
in transverse rows. This 
species 1s of European 
origin and was first dis- 
covered in the United 
States in 1925 near Som- 
erville, N. J. It is now 
known to occur im at least 
six counties in New Jer- 
in Michigan and Ohio. 
Also it was found for the 
first time in Canada at 
Windsor, Ontario, im 
1939. Reports from Eu- 
rope indicate that it isa 
serious defohator of pine 
and outbreaks occur at 
irregular intervals in 
Figure 147.—Larvae ot Neodiprion sertifier NY! countries on that 
showing gregarious feeding habits. continent. The discovery 
of this insect in the 
United States, its life history, and habits are discussed by Schaffner 
(374). 
The favored food plants in the United States include red, Scotch, 
Japanese red, jack, Swiss mountain, and mugho pines. Trees in New 
Jersey have been severely defoliated during the last few years. There 
is one generation annually and the life history 1s very similar to that 
of Neodiprion americanum. The larvae are gregarious and feed on 
the mature fohage, at first eating along the edges of the individual 
needles and later “devouri ing all the needles on one branch before mi- 
erating to another (fig. 47 ). Occasionally some of the cocoons are 
spun on the twigs of ae food plant, but generally they are spun in the 
duff under the trees. The fact that the larvae mature before the cur- 
sey and in some localities. 
