Project Spotlight: Greyrock Grazing Allotment Management Changes
The Greyrock Grazing Allotment stretches along the North Fork Poudre River above Seaman Reservoir to near Eagles Nest Open Space and includes about 2.5 river miles and riparian habitat.
by Dale Oberlag, North Zone Wildlife Biologist, Arapaho & Roosevelt National Forest and Pawnee National Grassland
The project area is within the Greyrock Grazing Allotment on the Canyon Lakes Ranger District, Roosevelt National Forest. It stretches along the North Fork Poudre River generally above Seaman Reservoir to near Eagles Nest Open Space and includes about 2.5 river miles and riparian habitat. Designated by U.S. Fish and Wildlife Service, this reach is in Preble’s mouse critical habitat. The allotment had been rested from grazing for several years up through about 2017. During the rest period, riparian shrubs (willows) grew back in abundance and expanded their presence along the stream, especially along the southern section. Herbaceous plants (sedges and grasses) in the riparian zone along the river typically would grow from about 2 to 3 feet tall. After resumption of grazing, there was a noticeable reduction in Preble’s mouse habitat conditions, although not all the corridor reflected such conditions. This was especially evident in 2021 and 2022 with conditions trending downward. Cattle grazed some areas more heavily, especially near river crossings, while some areas received little or no use. Although overall conditions were still meeting minimum habitat goals, increasing areas of short grazed and trampled herbaceous vegetation along the stream and damage to willows from cattle grazing and trailing through the willows were evident, both of which resulted in lower quality Preble’s mouse habitat. Because the 2021 and 2022 grazing season impacts were more substantial and trending in a downward direction, management changes to reverse this trend in reduced habitat conditions were considered.
For the 2023 grazing season, the permittee and Forest Service Range staff agreed to a modification of how he utilized the allotment. The permittee manages the allotment in 4 grazing areas in which he moves cattle through during the permitted grazing period. There are two grazing areas along the river corridor (southern and northern) and two upland grazing areas away from the river in the western part of the allotment. The goal was to reduce the time during which cattle grazed in the two river areas, which would be offset by a similar increase in grazing time in the upland areas. By reducing time along the river, this would reduce grazing impacts and result in improved Preble’s mouse habitat, specifically riparian and upland herbaceous vegetation height and riparian shrub/willow growth and form.
After the 2023 grazing season, immediate substantial improvement was observed. Improvements were even more dramatic after the 2024 grazing season (see photos below from September 17, 2024). After these two grazing seasons, the management and timing change has led to marked improvements in riparian and upland herbaceous habitat and Preble’s mouse habitat along the North Fork Poudre River corridor, achieving management objectives for the allotment.
