Wood samples extracted from western hemlock yield reproducible isotopic signatures (±1‰) and were highly variable among the seven trees (range minus 2.5‰ to + 2.5‰). The two control trees at Bulson Creek, where salmon were absent,both had d15N values near –2.5‰, and this wasindependent of their distance from the stream (F = 0.0, P = 1.0). Trees from the adjacent watershed at Warn Bay, where salmon are present, have d15N values ranging from –2.4‰ to +2.5‰, dependent on the distance from the stream (Figure1). The lowest value (–2.4‰) occurs in the tree furthest from the stream (34 m) and intermediate values (–1.5‰ to –0.5‰) occur in the two trees 10–15 m from the stream, while the highest values (1.5‰, 2.5‰) occur in the two trees closest to the stream (7 m, 4 m, respectively;F = 89.4, P < 0.001