Chronological dating of high-elevation dead and dying trees on northern Vancouver Island, British Columbia

We analyzed tree rings to determine the time of death for 18 moribund and d ead trees used as roosts by bats on northern Vancouver Island. We crossdate d 29 increment core samples with tree-ring chronologies of living trees to estimate when the trees died. After they die, yellow-cedar (Chamaecyparis n ootkatensis) trees deteriorate slowly and remain standing for as long as 20 0 years. In contrast, few western hemlock (Tsuga heterophylla) and western white pine (Pinus monticola) snags persist longer than 100 years. The ages at which our sampled trees died were highly variable, with western white pi ne, western hemlock, and yellow-cedar exhibiting the narrowest to widest ra nge of ages, respectively. Our findings highlight the long persistence of s nags in high-elevation coastal forests and the centuries of ecological serv ice that these trees provide to snag-dependent wildlife.