In some cases the area of discoloration expanded and involved the distal portion of the needle or the entire needle. Often this led to the shedding of those needles infected. In order to better understand the Grand fir survivorship, studies on stem wounding were carried out. This material is important in the defense against pest and pathogens and in wound sealing. The Western Spruce Budworm is a common herbivore that frequently infest mixed conifer forests.
Grand firs are also susceptible to the destructive ramifications of the budworm.
In an attempt to combat the effects of the budworm several studies have been carried out to enhance tree defenses. Community ecology and distribution of California hardwood forests and woodlands. This informative article provided extensive information related to the dynamics of California's hardwood forests and woodland. Furthermore, it provided information pertaining to disbursement, density and sucessional stages of specific trees and their associated plant species. Recent research on foliage diseases conference proceedings.