Pelletized inoculation of fire mosses in severely burned conifer forests overcomes initial barriers to Bryum argenteum establishment but does not increase cover

• Published in: Ecological engineering Vol. 176; p. 106513
• Main Authors: Grover, Henry S., Bowker, Matthew A., Fulé, Peter Z., Sieg, Carolyn H., Antoninka, Anita J.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.03.2022; Elsevier BV
• Subjects: Ant collection; Aquatic plants; Bryophytes; Bryum argenteum; Burned area rehabilitation; Ceratodon purpureus; Colonies; Coniferous forests; Conifers; Diatomaceous earth; Drought; Experiments; Extreme drought; Fires; Funaria hygrometrica; Inoculation; Mixed forests; Mosses; Soil; Soil surfaces; Tissue; Wildfires; Ant collection; Ceratodon purpureus; Funaria hygrometrica; Burned area rehabilitation; Bryophytes
• ISSN: 0925-8574; 1872-6992
• DOI: 10.1016/j.ecoleng.2021.106513

As wildfires increase in extent and severity, we need new tools to rehabilitate burned landscapes. We tested the effectiveness of adding fire moss tissue, produced in the greenhouse, as a bio-inoculant to severely burned soils in dry mixed conifer forests. We conducted three sequential experiments using knowledge gained from previous experiments to fine-tune fire moss delivery methods. The first two experiments began in July 2017, less than ten days after a wildfire in Arizona, United States. First, we added disaggregated (passed through a 2 mm sieve) cultivated moss tissue to burned soil surfaces, which was immediately collected by ants. In a second experiment, we added two preparations designed to reduce ant collection: moss rolled into pellets using diatomaceous earth and moss ground to a powder. Pelletization increased Bryum argenteum cover (F[3,55] = 12.32, p < 0.001) and the number of distinct moss colonies (F[3,55] = 11.87, p < 0.001) when compared to untreated control plots, although cover remained low (1%). A third experiment took place four months postfire in New Mexico. Sieved moss, pelletized moss, and pelletized moss at a high (5×) application rate were added to a burned forest. The high-rate pelletized treatment increased B. argenteum colony count by 140% compared to controls (F[3,44] = 2.37, p = 0.084), but did not increase cover (F[3,44] = 1.19, p = 0.325). At both sites, an extreme drought (Palmer Drought Severity Index < −4) during the winter of 2017–18 likely reduced success. We recommend further refinement and testing of pelletization in non-drought conditions. •Ant collection should be monitored for and mitigated during biocrust additions.•Pelletization of moss propagules increased colony counts 40-fold over control plots.•Vegetative propagules of C. purpureus and F. hygrometrica did not establish.•Trials in non-drought years are needed to better assess inoculation potential.