Medusahead: Available soil N and microbial communities in native and invasive soils

Abstract

To better understand why medusahead (Taeniatherum caput-medusae) is invasive, we quantified soil N availability and characterized soil microbial communities between native and invasive populations. No consistent differences in soil N mineralization potentials were noted between native medusahead sites in Spain, Turkey, France, and Greece and two invaded sites on the volcanic tablelands of northeastern, California, U.S.A. The proportional makeup of the microbial community, as quantified by phospholipid fatty acid analysis (PLFA), did not differ appreciably between a native site in southern France and one site on the tablelands of northeastern, California sites. Microbial markers indicative of growth phase suggest soils of invasive populations have higher turnover rates than native soil. No useable DNA could be extracted from the native medusahead soil in southern France using bacterial S16 ribosomal DNA. Tablelands soil contained distinct bacterial DNA bands for bacteria that utilize methane and methanol, anaerobically reduce sulfur, catabolize aromatics, for symbiotic relationships with root nodules of legumes. In summary, there is no definitive evidence in the studies carried out to indicate why medusahead is invasive in the Western United States.

Parent Publication

• Proceedings-Shrublands under fire: disturbance and recovery in a changing world; 2006 June 6-8; Cedar City, UT

Citation

Blank, Robert R.; Sforza, Rene; Morgan, Tye. 2008. Medusahead: Available soil N and microbial communities in native and invasive soils. In: Kitchen, Stanley G.; Pendleton, Rosemary L.; Monaco, Thomas A.; Vernon, Jason, comps. 2008. Proceedings-Shrublands under fire: disturbance and recovery in a changing world; 2006 June 6-8; Cedar City, UT. Proc. RMRS-P-52. Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station. p. 73-76