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.