Big Prairie
One attribute that the east and west sides of the park have in common is a major problem with exotic plant species. In the North fork prairies, leafy spurge and yellow toadflax have invaded disturbed areas and pose a major threat to native species. Control measures are very difficult, especially with the deep-rooted spurge.
On the east-side grasslands, non-native timothy grass was introduced intentionally for horse pasture in the 1920s or 30s, and spotted knapweed invades many disturbed areas. The spread of these exotic plants makes suitable grazing food unavailable to elk and deer, which impacts their populations along with predators. Only dogged, continuous control programs have any hope of reversing this trend.
