PITYOPHTHORUS ORARIUS BRIGHT (COLEOPTERA: SCOLYTIDAE) IN A NORTHERN CALIFORNIA DOUGLAS-FIR SEED ORCHARD: EFFECT OF CLONE, TREE VIGOR, AND CONE CROP ON RATE OF ATTACK
1994 ◽
Vol 126
(5)
◽
pp. 1111-1118
◽
Keyword(s):
AbstractThe geographic range of the Douglas-fir twig beetle, Pityophthorus orarius Bright, was extended beyond the original provenance of southern British Columbia to northern California. A survey of 457 Douglas-fir [Pseudotsuga menziesii (Mirb.) Franco] trees in 1985 revealed that those with heavy cone crops were more likely to be infested by twig beetles than were those with a light crop. Furthermore, attack rates differed among clones. A second survey done in 1987 confirmed the importance of clone and cone crop in attack rate. In this survey, stressed trees were attacked at a higher rate than unstressed trees. Beetle distributions appeared clumped in both surveys, possibly because of semio-chemicals or oviposition behavior.
1998 ◽
Vol 28
(8)
◽
pp. 1198-1206
◽
1995 ◽
Vol 52
(3)
◽
pp. 213-222
◽
2018 ◽
Vol 48
(7)
◽
pp. 809-820
◽
Keyword(s):
2010 ◽
Vol 40
(1)
◽
pp. 155-166
◽
Keyword(s):
Keyword(s):
1991 ◽
Vol 123
(6)
◽
pp. 1219-1228
◽