As the demand for agriculture grows, rangeland managers are charged with the task of managing larger and more complex operations. However, many rangelands (especially in predominantly livestock-agricultural states like Texas) are often too large and inaccessible to assess and monitor the health of vegetation by hand. In recent decades, since satellite imagery has become regularly available, rangeland managers have turned to remotely sensed methods of monitoring vegetative biomass and health.

https://sciencetrends.com/using-ndvi-and-osavi-to-monitor-rangeland-health