934 MISC. PUBLICATION 657, U. S. DEPT. OF AGRICULTURE 
KEY TO THE ROOT BORERS—Continued 
3. Mandible round at apex, pronotum smooth 
Aneflomorpha subpubescens, p. 246 
Mandible pointed at apex; pronotum roughened with fine points 
Oberea, p. 255 
Im sassabrasu ss) Ste acess eee eee eee O. ruficollis, p. 256 
LT sk SUMMA Coe es ee ee eee O. ocellata, p. 255 
In rhododendron and related plants_____ O. myops, p. 255 
KEY TO THE BORERS BENEATH THE BARK OR IN THE WOOD OF RECENTLY DEAD 
OR FELLED TREES 
In class VI are included those borers that usually attack wood only 
when the bark is present and still rather fresh and green. Nearly 
always, after the wood has seasoned from 4 to 6 months, it is immune 
to attack by these borers. Trees dying gradually are often subject 
to attack. These borers cause great losses in rustic work and log 
houses, also in lumbering operations where the trees cut during the 
winter are left lying on the ground throughout late spring and early 
summer. Cordwood and pulpwood are also damaged. 
The character of the frass is used here to distinguish certain species. 
In some forms it is fibrous or shredded, in others granular. This dis- 
tinction is not difficult to make, the only possible confusion arising 
from the plug closing the pupal chamber, which in nearly all forms 
is fibrous. 
ie Larvae foundsinvconiferous: tEeese 2) <a 2a a a ee eee ee 
Larvaefound in hardwood trees] 32-2 5-22) oa a ee ee eee 
2. Frass or boring dust behind larvae composed of granular, closely 
packed material (never fibrous or shredded, except in pupal cell)_ 
Frass or boring dust composed largely of fibrous or shredded 
material sso 2 ety ae Se SN ee Ee ee 
Frass cast out by larvae through a small hole___________________ 
Frass tightly packed behind larvae, filling entire larval mine____ 
4, Under side of head having four small tubercles; in pines, spruces, 
junipers, and cedars__Callidiwm antennatum; C. janthinum, p. 240 
Under side of head without tubercles, but as in figure; principally 
invicedars (ands JUDIpEers == 2 5- e e e  eeeeee Oeme, p. 257 
5. In cypress, last segment of larvae bearing two dark-brown spots 
beneath =. *o eee eee ere Physocnemum andreae, p. 259 
Injcedars,junipers;-and:Douglas-fir= <2 2 oats ee ee eee 6 
In ‘pines, spruces 2 2's 2 = ree 9 ps re eee 7 
6. Larvae having no ocelli and no spines on last segment 
Semanotus ligneus, p. 250 
Larvae having one ocellus and two small spines on last segment 
BDOVEs=). eae 2 Ya oe See Se nee eee Atimia confusa, p. 237 
le Head wider than long; form cylindrical: 
Larvae having two small spines on last segment above; 
mandible pointed at apex 
Asemum; Criocephalus; Nothorhina, p. 237 
Larvae without spines; mandible rounded at apex 
X ylotrechus, p. 270 
Head longer than wide; ampullae velvety pubescent; form 
depressed’... ees ee Se se eee ee ae, Acanthocinus, p. 236 
8. Head broader than long; last segment of body having two small 
dorsalispiness 2222-5 Asemum; Criocephalus; Nothorhina, p. 237 
Head broader than long, slightly keeled at sides; larvae very de- 
DIessede. a= ss 2S ae ere ee Stenocorus lineatus, p. 262 
Head longer than broad; last segment without spines 
Monochamus spp., p. 252 
9. Frass-entirely granular. 9 9) 2 =e eee eee 10 
Frass containing much fibrous material” 2-2 ose eee eee 11 
ey) On 
Sad 
Or Hs 00 
