Peck,
J.E. & B. McCune. 1998.
Commercial moss harvest in northwestern Oregon:
biomass & accumulation. Biological
Conservation, 86:299-305.
As
concern over the sustainability of commercial moss harvest in the Pacific
Northwest has grown, so too has the need to develop methods for estimating the
rate of harvest, the biomass inventory, and the rate of accumulation of
commercially harvestable epiphytes. We estimated biomass and net moss
accumulation in 10 sites in both the historically heavily moss-harvested Coast
Range and the historically relatively unharvested Cascade Range of northwestern
Oregon. Harvestable epiphyte biomass in the lower canopy (<2 m above
ground) ranged from c. 120 to 1470 kg/ha in the Coast Range, and 25 to 1068
kg/ha dry weight in the Cascade Range. The greater biomass at the Coast
Range sites resulted from a higher density of suitable substrates, with epiphyte
mass per unit area of substrate roughly equal in the two sets of sites.
Epiphyte mass accumulation of vine maple Acer circinatum was extremely
variable within and between sites, especially in the Coast Range. A model describing
the factors affecting epiphyte mat accumulation is described. We recommend
active management to conserve epiphytic bryophyte through promoting hardwood
tree and shrub substrates, restricting moss harvest to the lower canopy,
controlling the rate of harvest, and instigating rotation periods.