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Author Rizzo, D. M. ♦ Slaughter, G. W. ♦ Parmeter, J. R.
Source CiteSeerX
Content type Text
File Format PDF
Subject Domain (in DDC) Computer science, information & general works ♦ Data processing & computer science
Subject Keyword Fungal Pathogen ♦ Canopy Gap ♦ Yosemite Valley ♦ Potential Root Contact Zone ♦ Root Contact ♦ Potential Root Contact ♦ Fungal Competition ♦ Pon-derosa Pine ♦ Host Density ♦ Heterobasidion Annosum ♦ Gap Maker ♦ Adjacent Pine ♦ Gap-maker Diameter ♦ Enlargement Rate ♦ Variable-area Plot ♦ Sufficient Suitable Host Material ♦ Root Wood ♦ Actual Area ♦ Basal Area ♦ Gap Enlargement ♦ Tree Mortality ♦ Gap Margin ♦ Original Gap Maker ♦ Gap Perimeter
Abstract The pathogen is primarily spread among trees via root contacts; therefore, the spread and impact of H. annosum from the stump(s) where infection originated (gap makers) were characterized by describing the area of potential root contact as a variable-area plot. The potential root contact zone delineated the area that would be encompassed by mortality if all trees potentially in contact with the original gap makers had died. Of the 21 plots, the actual area of tree mortality exceeded the potential root contact zone in only two gaps. Enlargement rates around gap perimeters were uneven, rang-ing from 0 to 1.33 m/year. Incense-cedars (Calocedrus decurrens (Torr.) Florin) tended to die more slowly than pon-derosa pines (Pinus ponderosa Dougl.), often 10–30 years after adjacent pines had died. Gap enlargement was not dependent on host density, basal area, or gap-maker diameter, and tended to stabilize over time, probably because of fungal competition in root wood and lack of sufficient suitable host material along gap margins. Résumé: L’expansion de 21 trouées associées au champignon pathogène des racines, Heterobasidion annosum (Fr.:Fr.)
Educational Role Student ♦ Teacher
Age Range above 22 year
Educational Use Research
Education Level UG and PG ♦ Career/Technical Study