Induced resistance in wild tobacco with clipped sagebrush neighbors: the role of herbivore behavior

Previous experiments showed that wild tobacco plants with experimentally cl ipped sagebrush neighbors experienced less damage by grasshoppers than toba cco plants with unclipped sagebrush neighbors. This result could have been caused by grasshoppers preferring not to feed near clipped sagebrush. This hypothesis was tested in field choice experiments using six grasshopper spe cies feeding on an unresponsive and uniformly palatable food. When offered food that was either close to clipped sagebrush or close to unclipped sageb rush, grasshoppers showed no preference. When offered food that was either close to sagebrush (3 cm) or far from sagebrush (30 cm), grasshoppers prefe rred to feed far from sagebrush. However, this preference was similar wheth er or not the sagebrush had been clipped. Avoidance of feeding near clipped sagebrush, independent of changes in tobacco was not found to contribute t o our earlier result that tobacco near clipped sagebrush suffered less herb ivory than tobacco near unclipped sagebrush.