GROWTH-RATES OF 2 EPIPHYTIC CYANOLICHEN SPECIES AT THE EDGE AND IN THE INTERIOR OF A 700-YEAR-OLD DOUGLAS-FIR FOREST IN THE WESTERN CASCADES OF OREGON

Thalli of two epiphytic lichens, Lobaria oregana (Tuck.) Mull. Arg. and Pseudocyphellaria rainierensis Imsh., were collected from the canopy of an old-growth forest. Thalli were individually attached to nylon monofilament and transplanted into the crowns of four trees, two growing in the forest interior and two growing on the edge of a clearcut, at heights between 35 and 45 m above the ground. Half of the transplants in each tree were derived from thalli collected in the interior and half were derived from thalli collected on the edge. After one year, L. oregana transplants grew significantly less on the edge than they grew in the interior. The source of P. rainierensis thalli significantly affected transplant growth rate. Thalli that came from the interior and were transplanted to the edge did not grow, on average, while thalli that came from the edge and were transplanted back to the edge grew well.