Author: T. C. HarringtonPublisher:
ISBN:
Category :
Languages : en
Pages : 3
Book Description
Association of Black-stain Root Disease with Precommercial Thinning of Douglas-fir
Author: T. C. HarringtonBlack Stain Root Disease of Conifers
Author: Paul F. HessburgPublisher:
ISBN:
Category : Conifers
Languages : en
Pages : 12
Book Description
The Root Insect-- Black-stain Root Disease Association in Douglas-fir
Author: Jeffrey John WitcoskyPublisher:
ISBN:
Category : Douglas fir
Languages : en
Pages : 268
Book Description
Verticicladiella wageneri Kendrick is a vascular wilt pathogen of conifers, causing a black staining of colonized sapwood of roots and lower stem. In Douglas-fir, V. wageneri is intimately associated with insects. Hylastes nigrinus, Pissodes fasciatus, and Steremnuis carinatus are commonly associated with diseased hosts, carry inoculum of V. wageneri in the field, successfully transmit the pathogen to seedlings under laboratory conditions, and create suitable infection courts in susceptible hosts. Furthermore, insect-mediated transmission of V. wageneri has been documented tor the first time. Stand density management, such as precommercial thinning, results in elevated activity of H. nigrinu, P. fasciatus, and S. carinatus in disturbed stands. Insects colonize roots and the root collar region of cut trees; these hosts are susceptible to infection by V. waqeneri. Also, crop trees are wounded on the roots and root collar region by H. nigrinus for one to two years following precommercial thinning. Some of these wounds penetrate to the xylem and are, therefore, suitable infection courts for V. wageneri. Time of precommercial thinning can be manipulated to significantly reduce immigration of vectors, i.e., by thinning plantations during early summer after the peak flight of H. nigrinus. H. nigrinius and S. carinatus are attracted to alpha-pinene, a major constituent of Douglas-fir oleoresin. Forest management activities that injure hosts, and hence cause release of alpha-pinene, may attract vectors of V. wageneri. H. niqrinus and S. carinatus also are attracted to ethanol. In addition, root sections infected with V. wageneri are more attractive to H. nigrinus and S. carinatus than uninfected roots. Aspects of injury and stress to hosts leading to the release of host attractants are discussed. A crop production/pest management system structure is developed which links pest management activities for black-stain root disease prevention with normal intensive forest management. Pest management should be addressed at all stages of forest management: the harvest-establishment, annual, precommercial, and commercial phases of crop production.
Root Diseases in Coniferous Forests of the Inland West
Author: Publisher:
ISBN:
Category : Roots (Botany)
Languages : en
Pages : 40
Book Description
After nearly 100 years of fire exclusion, introduced pests, and selective harvesting, a change in forest composition has occurred in many Inland West forests of North America. This change in forest structure has frequently been accompanied by increases in root diseases and/or an unprecedented buildup of fuels. Consequently, many forest managers are implementing plans for fuels treatments to lower the risk of severe wildfires. Impacts on root disease should be considered before selecting appropriate fuels treatments. Complex interactions exist among conifer root diseases, fuels treatments, forest structure, species composition, stand history, and other environmental factors. As forest managers prescribe fuels treatments, their success in lowering the risk of severe wildfire will depend in part on the impacts of these treatments on root disease. Root diseases are one of many factors to be considered when developing plans for fuels treatments. Choices must be made on a site-by-site basis, with knowledge of the diseases that are present. This paper provides examples of how fuels treatments may increase or reduce specific diseases and demonstrates their importance as considerations in the fuels management planning process. Several root diseases prevalent within Inland West of North America are addressed: Armillaria root disease, annosus root disease, laminated root rot, black stain root disease, Schweinitzii root and butt rot, Tomentosus root disease, Rhizina root rot, and stringy butt rot. For each disease, general information is provided on disease identification, management options, and potential effects of fuels treatments. However, many long-term studies are needed to assess effects of specific interactions among fuels treatments, root diseases, and host trees.
Black Stain Root Disease in Douglas-fir on Jackson State Forest
Author: Raymond E. JackmanProceedings of the ... Annual Western International Forest Disease Work Conference
Author: General Technical Report RMRS
Author: Publisher:
ISBN:
Category : Forests and forestry
Languages : en
Pages : 260
Book Description
The Influence of Black Stain Root Disease on the Mortality and Growth of Douglas-fir Thinned to Various Spacings
Author: William B. MountPublisher:
ISBN:
Category : Douglas fir
Languages : en
Pages : 124
Book Description
Author: 
Author: