The Horse Creek unit is located on the North side of the North Platte River east of the Nebraska-Wyoming state line where Farmer's Irrigation District's TriState Canal diverts water from the North Platte River. The area encompasses approximately 500 acres of riparian river frontage, meadow and wetland. Some wetlands are sustained by seepage from the Tri-State irrigation canal. The aging old growth cottonwood and willow trees along the internal water course is home to a great blue herron rookery. Many white-tailed deer, turkey, and various species of waterfowl can be found on the area year around. Migrating waterfowl are found here in large numbers in the winter months. Bald Eagles can frequently be seen here during the winter. The area is heavily infested with salt cedar, Russian olive, and Canada thistle. Remnants colonies of native plant species such as snowberry, golden current, and choke cherries can still be found in some areas. Efforts to control the Russian olive infestation have met with limited success especially in areas where the groundwater levels rise when the Tri-State irrigation canal is flowing. Mature trees were pulled and stacked in the fall of the year. Sprouting from the roots which were left have resulted in tremendous numbers of trees taking the place of the larger trees removed by mechanical means. The piles have been chipped for mulch which is being used on community projects and other PRBE projects.