ARS | Publication request: Effects of Herbaceous Species Removal, Fire, and Cheatgrass (Bromus Tectorum) on Soil Nutrient Availability in the Sagebrush Steppe

Submitted to: Society for Range Management Meeting Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: September 1, 2003
Publication Date: June 26, 2004
Citation: Blank, R.R., Chambers, J. Meyer, S., Roundy, B.A., Whittaker, A., Korfmacher, J., Kitchen, S. 2004. Effects of herbaceous species removal, fire, and cheatgrass (bromus tectorum) on nutrient availability in the sagebrush steppe [abstract]. Society for Range Management 57th Annual Meeting, Salt Lake City, Utah. 57:37.

Technical Abstract: Soil nutrient availability is often a robust predictor of site invisibility by weedy species. We are using resin capsules to quantify soil nutrient availability by site (multiple elevations in Utah and Nevada), by fire treatment (burned and unburned), by degree of herbaceous vegetation removal, and by seeding regime (seeded with cheatgrass, unseeded). Resin capsules were placed in shrub interspace positions at 10 cm depth and left to integrate soil nutrient availability from about May through Oct. and from Nov. through April in 2001-2003. Data reported are for Nevada sites only. Complete herbaceous vegetation removal significantly (p=0.05) increased resin uptake of Ca (interaction with site) and N (main effect) relative to 0 and 50% removal. Relative to unburned controls, burning significantly increased resin-extractable Ca (interaction with seeding regime), K (interaction with site and collection date), Fe (interaction with seeding regime), Mg (interaction with site and seeding regime) and N (main effect). Several resin-extractable nutrients were significantly affected by seeding regime. Capsules placed beneath cheatgrass plants had significantly more Fe and Ca on burned treatments and significant less Fe and Ca on unburned treatments than capsules placed in non-seeded areas. These data demonstrate that soil nutrient availability can be considerable influenced by vegetation burning, by herbaceous vegetation management, and by the presence or absence of cheatgrass. We will continue to monitor sites for 2 more years concentrating on testing the hypothesis: does cheatgrass presence result in greater soil nutrient availability relative to native species.