Skip to Main Content
U.S. Forest Service
Caring for the land and serving people

United States Department of Agriculture

Home > Search > Publication Information

  1. Share via EmailShare on FacebookShare on LinkedInShare on Twitter
    Dislike this pubLike this pub
    Author(s): Walter G. Thies; Douglas J. Westlind
    Date: 2006
    Source: Forest Ecology and Management. 235: 212-218
    Publication Series: Scientific Journal (JRNL)
    PDF: View PDF  (230 KB)


    Phellinus weirii (Murr.) Gilb. causes laminated root rot (LRR), a major disease affecting growth and survival of Pseudotsuga menziesii (Mirb.) Franco (Douglas-fir) and other commercially important conifer species throughout the Pacific Northwest. This disease is known to spread to a replacement stand by root contact between replacement trees and residual infected stumps and roots from the harvested stand. One strategy to manage LRR is to reduce the residual inoculum on a site through application of a fungicidal chemical to infested stumps. The first two studies in this series established that chloropicrin (trichloronitromethane), applied to infested stumps, largely eliminates P. weirii from most of the belowground biomass and determined the effective dosage to apply. This third study approximated an operational application and based treatment success on reduction of LRR in the replacement stand. The study area was an 8-ha, 65-year-old naturally regenerated second-growth stand that was predominantly Douglas-fir. The stand was surveyed preharvest and postharvest (clearcut). Each P. weirii-infected entity (standing dead or down trees and stumps) was marked, and the location of its center was mapped. Circular plots (0.04 ha) were located so as to include concentrations of infested stumps. Plots were stratified based on their estimated biomass of inoculum into eight replicate blocks of four plots each. Three chloropicrin treatments and an untreated control were assigned randomly to four plots in each of the eight blocks: (a) 100% labeled dosage to all stumps, (b) 20% labeled dosage to all stumps, (c) 100% labeled dosage to only visibly P. weirii-infected (stump-top stain or advanced decay) stumps, and (d) control (nothing done to the stumps). Holes were drilled into stump tops, a dose of chloropicrin poured in, and the holes plugged. The labeled dosage was 3.3 ml of chloropicrin per kilogram of estimated stump and root biomass. Douglas-fir seedlings were planted in the winter following treatment application. When the stand was considered established, each plot was thinned to an inter-tree spacing of 2.4 m and the trees tagged. Diameter at breast height, total height, and mortality of trees were recorded every 2-5 years. A total of 1041 tagged trees were observed for 16 growing seasons following treatment. Application of chloropicrin to stumps in the harvested stand did not influence the rate of LRR-caused mortality or growth of Douglas-fir seedlings in the replacement stand.

    Publication Notes

    • You may send email to to request a hard copy of this publication.
    • (Please specify exactly which publication you are requesting and your mailing address.)
    • We recommend that you also print this page and attach it to the printout of the article, to retain the full citation information.
    • This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.


    Thies, Walter G.; Westlind, Douglas J. 2006. Application of chloropicrin to Douglas-fir stumps to control laminated root rot does not affect infection or growth of regeneration 16 growing seasons after treatment. Forest Ecology and Management. 235: 212-218


    laminated root rot, disease control, fumigation, chloropicrin, impacts, epidemiology

    Related Search

    XML: View XML
Show More
Show Fewer
Jump to Top of Page