Determining Sustainable Tree Moss Harvest Levels and Evaluating the Risk of Exotic Macroinvertebrate Introductions

EPA Grant Number: F6F10385
Title: Determining Sustainable Tree Moss Harvest Levels and Evaluating the Risk of Exotic Macroinvertebrate Introductions
Investigators: Peck, JeriLynn E.
Institution: University of Minnesota
EPA Project Officer: Hahn, Intaek
Project Period: September 1, 2006 through September 1, 2009
Project Amount: $111,172
RFA: STAR Graduate Fellowships (2006) RFA Text |  Recipients Lists
Research Category: Academic Fellowships , Ecological Indicators/Assessment/Restoration , Fellowship - Terrestrial Systems Ecology


This project aims to fill in the knowledge gaps required to develop regulation guidelines for the commercial harvest of the nontimber forest product of epiphytic moss. The recovery dynamics following simulated moss harvest will be evaluated by analyzing regrowth data taken in 2004 and 2005 on 6 Coast Range and 3 Cascade Range sites established in 1994. Using the 1994 data, I will compare the species composition of pre- and post-harvest moss communities. I will also compare the relative species composition of commercially sold moss to that found in field studies to verify that the species we think are predominantly harvested are in fact the ones that are harvested and subsequently sold. The hypothesis that the common and fast growing, though typically canopy-dwelling, moss Antitrichia curtipendula establishes in the understory primarily on existing Isothecium myosuroides mats as opposed to bare surfaces will be tested in artificial sowing experiments using A. curtipendula propagules in situ. Finally, the hypothesis that moss harvest may contribute to exotic introductions will be tested by extracting macroinvertebrates from bags of commercially sold tree moss.

The objectives of the proposed work are to parameterize an existing moss accumulation model and to determine the magnitude of risk for invasive species introductions.


The immediate approach will be to: a) measure the rate and dynamics of moss reaccumulation under natural conditions, including changes in diversity and species composition, by revisiting 10-11 year old research plots; b) test establishment and accumulation hypothesis through controlled experiments; and c) determine survival rates by extracting live macroinvertebrates from commercially harvested, stored, and shipped moss.

Expected Results:

I expect to find that (1) 10 years of regrowth will be insufficient to develop mature moss mats, (2) necessary rotation periods will be 20-40 years, (3) diversity will be lower, and composition altered, immediately following harvest, (4) very young/small mats will have high evenness, moderate mats will be primarily composed of the typical dominant species and hence less diverse, and very large, old mats will be more diverse, (5) species composition of sold material will be comparable to that found in situ, (6) a threshold exists in both propagule size and host mat size after which establishment and growth of A. curtipendula is enhanced, and (7) numerous macroinvertebrate taxa survive commercial processing and shipping, at least some of which may be invasive.

Supplemental Keywords:

moss harvest, NTFP, SFP, epiphyte, bryophyte, macroinvertebrate, succession, rotation period, regrowth, establishment,, Scientific Discipline, Ecosystem Protection/Environmental Exposure & Risk, Habitat, Environmental Monitoring, Ecological Risk Assessment, habitat dynamics, biodiversity, tree moss harvesting, habitat disturbance, ecological consequences, forest canopy monitoring, invasive species, forest conservation

Progress and Final Reports:

  • 2007
  • 2008
  • Final