Chamaecyparis lawsoniana - large timber tree of western North America with trunk diameter to 12 feet and height to 200 feet Lawson's cedar, Lawson's cypress, Oregon cedar, Port Orford cedar cedar, cedar tree -
Acute infection of Chamaecyparis lawsoniana var. ellwoodii by Phytophthora cinnamomi occurred when many zoospores were present and the roots were growing actively. Active root growth occurred during periods of long day-length. It is suggested that chronic infection results when few zoospores are present...