Initial response of Arabis johnstonii Munz to fire

Abstract

Arabis johnstonii Munz (Johnston’s rock cress) is a small herbaceous perennial plant endemic to the San Jacinto Mountains of southern California. It is considered rare by the California Native Plant Society and is a Forest Service Sensitive species. Three A. johnstonii occurrences grow within an area that the San Bernardino National Forest plans to burn for hazardous fuel reduction. Prior to this study little was known about fire effects on A. johnstonii. We used a 1.1 m diameter cylindrical stainless steel wire “fire cage” within which we conducted small-scale experimental burns on twenty clusters of A. johnstonii. Weather, fuel conditions, and fire behavior were recorded during burns conducted in September 2003 and January 2004. A. johnstonii survival, growth and recruitment will be measured twice a year for up to three years after the fires. About five months after the first experimental burn, most A. johnstonii were still alive, but they were generally smaller and shorter than unburned individuals. Burned A. johnstonii showed no change in numbers of individuals compared to pre-burn counts, however unburned plot numbers increased by 15 percent over the same time period.

Parent Publication

• Southwestern rare and endangered plants: Proceedings of the Fourth Conference

Citation

Narog, Marcia G.; Sclafani, Christie J.; Escobar, Christina; Kramer, Kate A.; Beyers, Jan L. 2007. Initial response of Arabis johnstonii Munz to fire. In: Barlow-Irick, P.; Anderson, J.; McDonald, C., tech eds. Southwestern rare and endangered plants: Proceedings of the Fourth Conference; March 22-26, 2004; Las Cruces, New Mexico. Proceedings. RMRS-P-48CD. Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station. p. 83-92