Exploring Fire Moss in the Northwest

When I tell people that I study mosses in Arizona and New Mexico some folks give me a quizzical look and ask why I’m not working up in the Northwestern US. Thanks to the support of Jason Jimenez from the Colville National Forest and Pete Robichaud from the RMRS Moscow Forest Sciences Laboratory I have been able to heed that advice. Over the past two summers I have traveled to Kettle Falls, Washington to help monitor a Burned Area Emergency Response (BAER) mulching treatment on the 2015 Stickpin Fire. This has also fed my summer wanderlust as I have expanded my natural survey of fire moss colonization to the 2015 fires in Washington and the 2017 fires in Montana.

The Sunrise Fire of 2017, Quartz Montana

It was incredible to see just how important moss is for postfire recovery up there, everything that north westerners had told me was true! I saw the usual suspects Funaria hygrometrica and Ceratodon purpureus, and some new early successional species, Polytrichum juniperinum and the liverwort Marchantia polymorpha. One species that was conspicuously absent from the Northwest was Bryum argenteum. Total bryophyte cover was over 50%! And the speed of natural colonization and succession was incredible. After exploring fires less than one year old, it became apparent that moss was the largest contributor to cover immediately after fire, and thus is an important component of soil stabilization in this region.

Some crispy Marchantia and Funaria both releasing spores prolifically, two years after fire

Moss colonizing the Noisy Creek fire spring 2018, 8 months after fire

To better understand how mulching affected moss colonization on the Stickpin fire, I trained the soils crew from the Colville NF on my methods. Last fall, they sampled straw and wood shred mulched units, as well as an untreated unit. Moss cover was significantly lower on both of the mulches, but seemed to fill in around and under them quite well.

Maddie and Amber demonstrating perfect bryophyte sampling technique. It has been wonderful to share my research with land managers and learning from their experience in a new ecosystem. 

Moss eking out a living under low cover straw mulch.

We were interested in exploring mulching impacts byrophytes in more detail. Additionally we wanted to understand how postfire logging affects moss cover on a logging experiment that had occurred close by. Both mulching and logging are relatively common postfire management techniques and their impacts on vascular plants has been studied in detail. Broyphytes have received much less attention so I submitted a Joint Fire Science Program GRIN proposal to expand our research and it was funded! We will continue to monitor the impacts of postfire treatments on bryophytes this fall and will add some plots in logging units. We will also measure the impacts of mulching and logging on available soil nutrients and relate that to bryophyte cover. Finally, a major component of the GRIN is outreach to the management community so I will be attending BAER workshops, giving a webinar, and creating a fact sheet to continue sharing my research with land managers.