Title: Bark beetle risk in mature ponderosa pine forests in western Montana
Identifier: barkbeetleriskin119john (find matches)
Year: 1972 (1970s)
Authors: Johnson, Philip C. (Philip Cornwell), 1907-; Intermountain Forest and Range Experiment Station (Ogden, Utah) 1n
Subjects: Bark beetles Montana; Ponderosa pine Diseases and pests Montana
Publisher: Ogden, Utah : Intermountain Forest & Range Experiment Station, Forest Service, U. S. Dept. of Agriculture
Contributing Library: U.S. Department of Agriculture, National Agricultural Library
Digitizing Sponsor: U.S. Department of Agriculture, National Agricultural Library

View Book Page: Book Viewer
About This Book: Catalog Entry
View All Images: All Images From Book
Click here to view book online to see this illustration in context in a browseable online version of this book.

Text Appearing Before Image:
Figure 3.—Dense stand of advanced reproduction of Rocky Mountain Douglas- fir under a well-stocked overstory of mature ponderosa pine on a risk rating plot in the Piquett Creek Experimental Area, Bitterroot National Forest, Montana.
Text Appearing After Image:
The serai nature of ponderosa pine in most of the plot stands is only partially indicated by these nonpine tree species in the overstory. More conclusive evidence of ponderosa pine's serality in the plot stands is the intrusion in recent years of increas- ing amounts of nonpine reproduction in the understory stands of the plots. Dense stands of Rocky Mountain Douglas-fir, in particular, now occupy the ground under the pine canopy on parts of some plots (fig. 3). Stimulated by effective control of wild- fires and by growing conditions that have favored nonpine species during the past three decades, resultant nonpine reproduction is preventing or crowding that of ponderosa pine in many of the plot stands. Observations disclosed that the pine understory on most of the plots was so sparse that its maturation will produce timber yields far short of those expected from ponderosa pine site indexes 70, 80, or 90 that the plots represent (Meyer 1938). The mean stocking density for all species ranged for each plot stand from 14.7 to 44.9 trees per acre (12,920 to 25,730 gross board feet per acre). The mean stocking density for ponderosa pine alone ranged for each plot stand from 14.7 to 37.3 trees per acre (9,990 to 25,200 gross board feet per acre) (fig. 4). The stocking densities for pine and nonpine species are shown for each of the 35 plots in tables 1 and 2. 9

Note About Images