Western redcedar seed, a food of pine siskins

Destruction of forest tree seed has a direct influence on the amount ofregeneration in the Douglas fir (Pseudotsuga menziesii) region of the PacificNorthwest. Land managers are becoming increasingly concerned aboutgetting deforested areas back into tree production as soon as possible. Anyinformation relative to this problem adds to the overall knowledge and helpsto form a sounder basis for management. Western redcedar (Thuja plicata)is an important timber species in Douglas-fir forests. General observationsof pine siskins (Spinus pinus) over an 11-year period and analysis of siskinstomachs suggest that western redcedar seed is an important fall, winter,and spring food of the species on the H. J. Andrews Experimental Forest,located within the Willamette National Forest in Linn and Lane counties,Oregon. The siskin specimens were collected in the spring of 1957 in con-nection with a study of animal influences of forest reseeding. A reasonablythorough perusal of the literature failed to produce any reference to westernredcedar seed as a siskin food. Fowells (1965) lists only rodents as possibledepredators on artificially and naturally cast seeds of the redcedar.