tl SEEPS SE 2 es EE ee 
The adult is reddish-brown to black and about 2.3 to 2.8 mm. 
long. The declivity is shallowly excavated and deeply punctured. 
Each side is armed with four small teeth and the apical margin 
is slightly produced. One to several long, winding egg galleries 
originate from a central nuptial chamber (fig. 97). Larval gal- 
leries are short, transverse, and each ends in a pupal cell in the 
phloem. In the south, the life cycle may be completed in 18 to 25 
days, and there may be 10 or more generations per year. 
COURTESY OF 
DUKE UNIV. SCH. OF FOREST. 
FIGURE 97.—Galleries of Ips 
avulsus in bark of short- 
leaf pine. Note radiate 
tunnels of adults, short 
larval mines, and pupal 
chambers. 
YE 
i MEN. e 
Tha iv u 
The pine engraver, Jps pini (Say), occurs throughout the boreal 
forests of North America and south to Tennessee in the Eastern 
States. It breeds in several species of spruce and probably all 
Species of pine within its range. Infestations usually develop in 
slash and windfalls or in trees dying of other causes. When heavy 
populations build up in this type of material, nearby healthy 
trees may be attacked and killed. Heavy infestations have oc- 
curred in cut-over and burned-over areas in Canada. 
The adult is brown to black, is from 3.5 to 4.5 mm. long, and 
has four teeth on each side of the declivity. Egg galleries, from 
three to six, radiate away from a central nuptial chamber in the 
phloem, deeply scarring the sapwood. Larval tunnels extend a 
short distance in the inner bark and end in pupal cells. Adults 
remain under the bark for a short period before emerging. While 
there, they eat irregular, meandering food tunnels, deeply en- 
graving the wood. Winter is spent in the adult stage on the 
ground. There appears to be three generations per year as far 
north as Wisconsin (641). 
Other less common eastern species of Jps include: (1) J. per- 
turbatus (EHichh.)—breeds in white spruce in the Lake States 
and Canada. (2) I. perrott Swaine.—breeds in red and jack pines 
in Minnesota. (3) J. borealis Swaine.—breeds in spruce in the 
Lake States. (4) J. latidens (LeC.).—breeds in white, red, jack, 
and Scotch pines, white spruce, and hemlock in the Lake States. 
The genus Orthotomicus Ferrari is represented by two species 
in eastern forests. It is closely related to the genus /ps, but the 
adults differ in having obliquely truncate antennae and feeble 
teeth on the margin of a shallow concave declivity. 
262 
