Submitted to: Weed Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/16/2013
Publication Date: 4/1/2014
Citation: Sheley, R.L., Sheley, J.L., Smith, B.S. 2014. Cost/benefit analysis of managing annual invasive grasses in partially invaded sagebrush steppe ecosystems. Weed Science. 62(1):38-44. DOI: 10.1614/WS-D-13-00056.1.
Interpretive Summary: Invasive annual grasses are creating vast monocultures of once productive rangeland across the west. Among the more commonly used methods for reducing annual grass infestations are herbicide applications and grazing management. How a manager bases decisions on treatments used to control invasive plants are dependent on a number of factors, however understanding the cost/benefit potential of options could be valuable to know before beginning control efforts. We evaluated a model developed by Griffith and Lacey (1991) used to evaluate the economics of spotted knapweed control using picloram. In this paper, we used their model to evaluate the cost/benefit of two different treatments, a single herbicide application or targeted grazing of annual grasses of partially invaded sagebrush steppe ecosystems used for livestock production. In our evaluation we found the present value of after-tax treatment herbicide costs could be paid to break-even using our vegetation response scenario was as high as $44.30 and as low as $12.52 per hectare depending on the level of utilization of invasive grasses the livestock consumed, using a single herbicide application. For a grazing treatment, we found the present value of after-tax treatment grazing costs were about $6.18 per hectare, whereas the value of added AUMs was as high as $32.12 and as low as $14.82, per hectare depending on the level of invasive weed utilization. Our assessment suggests that grazing management of rangelands with invasive annual grass infestations can be cost-effective based on vegetation changes that shift plant communities toward desired forage for livestock.
Technical Abstract: Our objective was to evaluate the cost-benefit of a single herbicide application or targeted grazing of annual grasses during restoration of partially invaded sagebrush steppe ecosystems used for livestock production. The cost/benefit model used is based on estimating the production of vegetation in response to implementing management and modeling cost/benefit economics associated with that prediction. The after-tax present value of added AUMs obtained was lower than the present value of after-tax treatment cost after 20 years for a single herbicide treatment, but higher than the present value of after-tax treatment costs for the grazing management scenario. This assessment clearly shows grazing management can be economically viable for managing annual grass infested rangeland. In the future, models like the one used here can be improved by incorporating the rangeland management and restoration benefits on the wide variety of goods and services gained from rangeland.