Date of Award:


Document Type:


Degree Name:

Master of Science (MS)


Wildland Resources

Committee Chair(s)

Eugene W. Schupp


Eugene W. Schupp


Janis L. Boettinger


Eric T. Thacker


Matthew C. Reeves


The Uintah and Ouray Reservation in northeastern Utah has not been widely studied, and access to non-tribal members is highly restricted. We sampled vegetation to summarize condition in 300,000 acres of unsurveyed Reservation lands in 2017-2018, combining these data with data collected by the Bureau of Indian Affairs from 2010-2015 to complete an initial rangeland vegetation inventory of the Reservation. This survey was designed to inform management of the area by determining cattle stocking rates and overall ecological condition across the Reservation. Both the density of forage available to cattle and appropriate cattle stocking rates vary greatly throughout management units in the Reservation.

We also used the vegetation inventory data to run a model which estimates forage availability in every year from 1984-2018 throughout the Reservation. Whereas the initial inventory only considers the typical forage availability in management units, this method allows us to estimate how forage varies through space and time. The results show that forage availability varies significantly through time, declining and increasing by approximately one-third from median forage availability.

Such variability indicates that typical forage availability, the measure used to determine stocking rates in the initial inventory, does not fully address forage availability dynamics. Since actual forage availability can be far lesser or greater than typical forage availability, stocking rates based on typical availability will often be an under or over estimation. The model results therefore lend a fuller picture of appropriate stocking rates. This may improve grazing management by revealing how much forage declines in unfavorable years such as during drought, and improving grazing planning during these years. The forage availability model can continue to be used in the future to monitor trends in vegetation over time, and the modeling method may be applicable to other similar study systems.