Article Terrestrial Bryophyte and Lichen Responses to Canopy Opening in Pine-Moss-Lichen Forests Dale H. Vitt 1,*, Laura Finnegan 2 and Melissa House 1 1 Department of Plant Biology, Southern Illinois University, Carbondale, IL 62901, USA;
[email protected] 2 Caribou Program, fRI Research, Hinton, AB T7V 1V3, Canada; lfi
[email protected] * Correspondence:
[email protected]; Tel.: +1-618-453-321 Received: 21 January 2019; Accepted: 1 March 2019; Published: 6 March 2019 Abstract: Pinus contorta-dominated montane forests of western Canada with relatively dense tree canopies have ground layers with abundant bryophytes, especially the feather mosses (Pleurozium schreberi and Hylocomium splendens), while those with more open canopies are dominated by species of reindeer lichens, especially Cladonia arbuscula s.l. and C. rangiferina s.l. Woodland caribou (Rangifer tarandus caribou), which are a threatened species in Alberta, prefer open, Cladonia-dominated forests for their winter food supply. This study investigated if opening the canopy by thinning mature montane forests of the Canadian Rocky Mountain foothills would change the abundance of lichens and bryophytes. In 1997, forests were thinned by removing 20%, 40%, and 60% by volume. In 2016, 19 years after treatment, we re-surveyed a subset of these plots (n = 97) for lichen and bryophyte abundance and species richness by utilizing the amount of canopy opening at the plot level as our prime gradient. We then used ordination to determine the relationship of control plots to treatment plots. In uncut forest, the control plots were highly variable, but were mostly dominated by feather mosses, with little or no bare ground.