Invasion Severity Index (CO)

This layer provides information on invasive annual grasses and the Invasion Severity Index (ISI). The ISI is a strategic planning tool designed to prioritize invasive annual grass management across the sagebrush biome. Using 10-meter resolution data from the Rangeland Analysis Platform, the ISI assesses the severity of annual grass invasion relative to perennial vegetation and bare ground. This layer categorizes the landscape into five levels ranging from intact cores to high-severity states with recommended management activities from maintaining to revegetating.

Tilley, D., Maestas, J., Smith, J., Mueller, K., Morford, S. and D. Naugle. 2026. Invasion Severity Index: Maps and Web App to Support Strategic Invasive Annual Grass Management. Working Lands for Wildlife. https://www.wlfw.org/invasion-severity-index/