@article {EFP:EFP167, title = {Pathogenicity of Phytophthora species to Pacific Northwest conifers}, journal = {European Journal of Forest Pathology}, volume = {12}, number = {3}, year = {1982}, pages = {167{\textendash}174}, publisher = {Blackwell Publishing Ltd}, abstract = {

Phytophthora root rot is described for the first time killing sugar pine (Pinus lambertiana) in a seed orchard and four species of true fir (Abies spp.) in a forest nursery. P. cactorum was recovered from true firs and P. megasperma was recovered from sugar pine. P. cryptogea was recovered from sugar pine and true fir but isolates from the two locations differed from each other in pathogenicity and colony appearance. Isolates recovered from these hosts and isolates of 6 Phytophthora species previously recovered from Douglas-fir (Pseudotsuga menziesii) were then tested for pathogenicity on seedlings of 9 Northwest conifers. P. megasperma Group 1, P. cryptogea, and P. cinnamomi were pathogenic to all tree species except western redcedar (Thujaplicata). Western hemlock (Tsuga heterophylla) and true firs were susceptible to most species tested; ponderosa (P. ponderosa) and sugar pines were damaged only by P. cryptogea and P. cinnamomi; western redcedar was resistant to all isolates.

}, issn = {1439-0329}, doi = {10.1111/j.1439-0329.1982.tb01390.x}, url = {http://dx.doi.org/10.1111/j.1439-0329.1982.tb01390.x}, author = {P.B. Hamm and Hansen, E.M.} } @article {654, title = {Phytophthora pseudotsugae, a new species causing root rot of Douglas-fir}, journal = {Can. J. Bot.}, volume = {61}, year = {1983}, pages = {2626{\textendash}2631}, abstract = {

Phytophthora pseudotsugae n. sp. was isolated from rotted roots of Douglas-fir growing in forest tree nurseries in Oregon and Washington. It is distinguished by large oogonia and oospores, mostly paragynous antheridia, and predominantly spherical or ovoid, persistent sporangia borne primarily on simple and unbranched sporangiophores. Sporangia are formed occasionally in liquid culture, rarely in solid media. Phytophthora pseudotsugae is distinguished most readily from P. cactorum by its unbranched sporangiophores and persistent sporangia. It also differs in growth on defined media, electrophoretic protein patterns, and pathogenicity. Comparison is also made with P. iranica, the other species in group 1 of Waterhouse.

}, doi = {10.1139/b83-289}, url = {http://rparticle.web-p.cisti.nrc.ca/rparticle/AbstractTemplateServlet?calyLang=eng\&journal=cjb\&volume=61\&year=1983\&issue=10\&msno=b83-289}, author = {P.B. Hamm and Hansen, E.M.} } @article {200, title = {Improved method for isolating Phytophthora lateralis from soil.}, journal = {Plant disease}, volume = {68}, year = {1984}, month = {June 1984}, pages = {517-519}, issn = {01912917}, doi = {10.1094/PD-68-517}, author = {P.B. Hamm and Hansen, E.M.} } @article {hamm1987identification, title = {Identification of Phytophthora spp. known to attack conifers in the Pacific Northwest}, journal = {Northwest Sci.}, volume = {61}, year = {1987}, month = {1987}, pages = {103-109}, publisher = {WSU Press}, author = {P.B. Hamm and Hansen, E.M.} }