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Large ares (6 million ha) of the United States and Canada, classified as range, have an enormous impact on the economy and environment through grass production. Production is often drastically reduced by infestations of grass-feeding insects. Although the literature is voluminous with references dealing with responses of agronomic crop plants to attacks by these insects, little research has been conducted on range grasses. The black grass bugs, Labops spp and Irbisia spp (Hemiptera: Miridae), are economically important on rangeland of the Intermountain West. The recognized mechanisms of plant resistance to insects are nonpreference, tolerance, and antibiosis. Trichome length and density within species of wheatgrasses (Agropyron sp) are negatively correlated with feeding behavior of the early instars of Labops hesperius Uhler, but not with older instars or adults. Certain species of wheatgrasses show varying degrees of tolerance to feeding by L. hesperius. Approximately 3,000 chemical compounds afford plants some protection against insects. During their long co-evolution with plants, however, insects overcame the toxic effects of many chemical compounds. Essentially no plant breeding has been done to develop range grass cultivars that are resistant to black grass bugs. Nevertheless, the opportunities are as great as the need that must be met if western rangelands are to satisfy multiple demands the future is likely to impose on them. This material was digitized as part of a cooperative project between the Society for Range Management and the University of Arizona Libraries. The Journal of Range Management archives are made available by the Society for Range Management and the University of Arizona Libraries. Contact lbry-journals@email.arizona.edu for further information. Migrated from OJS platform August 2020