Abstract
The boles of 32 recently killed, and 41 living, white fir were examined for embedded fir engraver (
Scolytus ventralis) attack scars. Of 287 scars found in annual rings for the years 1934-69, only 2 to 3 percent represented reproductively successful attacks. Trends in scar abundance were directly correlated with trends in white fir killed by
S. ventralis on 15 plots from 1939 to 1954. Influence of weather, host tree growth, and logging on yearly abundance of scars was examined by multivariate regression analysis. Years with increased scar abundance were preceded by at least 1 year of subnormal precipitation and coincided with subnormal tree growth. High peaks occurred when these conditions were contemporaneous with logging in the stand.
Keywords
Scolytus ventralis,
Abies spp.,
mortality,
drought effects,
logging effects,
growth vigor,
timber management,
Shasta County, California
Citation
Ferrell, George T. 1973. Weather, logging, and tree growth associated with fir engraver attack scars in white fir. Res. Paper PSW-RP-92. Berkeley, CA: Pacific Southwest Forest and Range Experiment Station, Forest Service, U.S. Department of Agriculture; 11 p