Peck, J.E. & P. Muir.  1998.  Towards sustainable commercial “moss” harvest.  Report to the Eugene District Bureau of Land Management, Eugene, OR.

To address the growing need for inventory estimates for the special forest product of epiphytic moss, we developed, tested, and calibrated a rapid inventory method suitable for use in ³50 year old upland and riparian forests below 915 m in central western Oregon.  Using a definition of “commercially harvestable moss” based upon recent conversations with commercial moss harvesters, we initially outlined a number of potential inventory methods.  After a five-plot pilot study, in which several inventory methods were compared for speed, accuracy, and precision, we refined these techniques and employed them in an additional 25 plots in riparian and upland forest in matrix, AMA, and LSR forest on the Eugene District, BLM, and the Sweet Home R.D., Willamette National Forest.  Site and stand characteristics were measured at each plot, as well as whole- and subplot level estimates of the number of trees and shrubs, of the number bearing harvestable mats, and of the number of harvestable mats on those trees and shrubs.  All commercially harvestable moss was then harvested from each plot using methods commonly employed by commercial harvesters.  Data from these 30 permanent plots were used to develop  regression models to predict plot-level harvestable moss biomass.  Several versions of the index were derived and their predictive accuracy compared.  These “indices of harvestability” will allow rapid estimation of harvestable moss biomass for forest plots in the study region.  To enable precise future stem-level estimates of reaccumulation rates, the volume and species composition of 0.3 - 2.0 m long harvestable moss mats, and the cover of all species remaining on the stem following harvest, were recorded on 5-20 permanently marked stems in the 13 plots that had harvestable quantities of moss.  We also conducted detailed surveys of bryophyte species composition in 23 of the plots.  This document represents the final report for the project to develop the index and an interim report for the project to implement it.  This document also includes:  a preliminary discussion of the site characteristics conducive to the development of harvestable moss biomass, written instructions and maps for re-locating plots and permanently marked harvested shrub stems, electronic spreadsheets with all site and biomass data, a methods manual and datasheets for future remeasurements of these plots, a list of the 1998 implementation plots, and a methods manual and datasheets for inventorying future plots.


PNW Moss Lit