Publication Details

Response of smooth rock skullcap (Scutellaria saxatilis), a globally rare plant, to fire

Huebner, Cynthia D.; Karriker, Kent

Year Published

2015

Publication

Res. Pap. NRS-28. Newtown Square, PA: U.S. Department of Agriculture, Forest Service, Northern Research Station. 16 p.

Abstract

Scutellaria saxatilis Riddell (smooth rock skullcap or rock skullcap, hereafter abbreviated as SRS), a herbaceous perennial in the mint family, is a globally rare (G3) plant. In West Virginia, SRS is categorized as an S2 species (imperiled and at high risk of extinction due to a very restricted range, very few [<20] documented occurrences, or steep declines). The purpose of this study was to determine the effects of fire on SRS in West Virginia. Two forested sites (70+ years of age) within the Monongahela National Forest with no evident disturbance and with SRS populations of >1,000 individuals were selected, one in a burn area and the other in a nonburn area. Sites were sampled in early September of 2008 and 2009 (pre-burn) and 2010 and 2011 (postburn). The prescribed burn occurred in April and early May of 2010. A generalized linear mixed model with repeated measures and a spatial covariance matrix was used to determine the effects of the burn on SRS cover and associated variables including total vegetation cover, species diversity, bare ground, and litter cover. Bare ground cover increased and litter cover decreased in 2010 in response to the fire. Control and pre-burn sites did not differ significantly in terms of SRS cover over the 4-year period. The cover of SRS increased significantly in 2010 (first year postburn) compared to both pre-burn years, but decreased to pre-burn levels by 2011. Total cover of other understory vegetation increased significantly in 2010 and continued at 2010 levels in 2011 at the burn site. Thus, SRS has a temporary positive response to prescribed fire, but an increase in other ground vegetation may prevent a sustained positive response.

Citation

Huebner, Cynthia D.; Karriker, Kent. 2015. Response of smooth rock skullcap (Scutellaria saxatilis), a globally rare plant, to fire. Res. Pap. NRS-28. Newtown Square, PA: U.S. Department of Agriculture, Forest Service, Northern Research Station. 16 p. https://doi.org/10.2737/NRS-RP-28.

Last updated on: April 24, 2015