Some prominent tallgrass prairie grasses include big bluestem, indiangrass, and switchgrass. Vegetation is predominantly blue grama, little bluestem, bunchgrass, buffalograss, wheatgrass, and green needleleaf. These endangered remnants include Indian grass, little bluestem, big bluestem, sideoats grama, and switchgrass. Prairie openings contained little bluestem and other grasses and forbs. The tallgrass prairies included little bluestem, big bluestem, yellow indiangrass, and tall dropseed. Midgrass and shortgrass species include little bluestem, side oats grama, and buffalograss. The caterpillars feed on grasses such as big bluestem and switchgrass. Big bluestem is a perennial warm-season bunchgrass. The mixed deciduous savannas have scattered eastern cottonwoods with little bluestem grass. Big bluestem is a mid-successional grass in prairie and other grassland ecosystems. A few dry, sunny knolls support prairie characterized by big bluestem and indian grass. Bearberry and little bluestem grass are the dominant plants. Little bluestem is the official state grass of Nebraska and Kansas. The most stable population occurred on unburned big bluestem ("Andropogon gerardii")-dominated plots.