Date of this Version
Great Plains Research 19 (Fall 2009):179-86
A study of feeding preference was conducted on two tallgrass prairie grasshopper species, the autumn yellow-winged grasshopper Arphia xanthoptera (Burmeister) and the short-winged green grasshopper Dichromorpha viridis (Scudder), to determine if they would feed upon introduced grass species. Both grasshoppers were offered two non-native cool-season grasses, smooth brome (Bromus inermis Leyss) and Kentucky bluegrass (Poa pratensis L.), and two native warm-season grasses, big bluestem (Adropogon gerardii Vitman) and sideoats grama (Bouteloua curtipendula Michx.). Live biomass of the plants was weighed before and after feeding to quantify the amount of each plant species consumed by the grasshoppers. Statistical analysis showed that D. viridis strongly preferred smooth brome (P ≤ 0.05) over other species offered. A. xanthoptera also consumed more smooth brome than the other grass species offered. These results suggest that both grasshopper species accept non-native grasses and perhaps prefer them to tallgrass prairie species. Because the tallgrass prairie ecosystem of the Great Plains has been dramatically impacted by human activity, documentation of the response of native insects to incursion by exotic plants is important to preservation efforts. Moreover, if grasshoppers feed on invasive sod-forming species such as smooth brome and Kentucky bluegrass, they may become an important ally in maintaining native plant diversity in remnant grassland ecosystems.