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Native larkspurs (Delphinium spp.) are damaging poisonous plants to livestock on western rangelands. Cattle death losses to larkspur poisoning have remained surprisingly consistent throughout the past century. Efforts to avoid larkspur poisoning of cattle result in significant lost opportunities to harvest forage. Larkspur management strategies have been developed, however most are specific to ‘tall larkspurs' and few options exist for ‘low larkspur'. Broadleaf selective herbicides may be used but these products reduce other perennial forbs and may amplify future larkspur problems by reducing effective competitors. This study was conducted to determine whether seeded native or introduced forbs would emerge in existing stands of Geyer's larkspur (Delphinium geyeri), and whether light-rate herbicide application, prior to seeding, would increase emergence of seeded forbs. Nine treatment combinations were replicated 3 times at 3 locations. Treatments consisted of all combinations of seeded forbs (native, introduced, and unseeded) and herbicide (2,4-D LV4, picloram, and unsprayed). Herbicides reduced larkspur density one year after treatment and no difference was detected between herbicides. Effects of herbicides on larkspur canopy cover one year after treatment were not obvious. 2,4-D reduced canopy cover of non-target forbs compared to the unsprayed and picloram treated plots. Canopy cover of non-target forbs in unsprayed plots was similar to plots treated with picloram at two of the three locations. Density of seeded forbs was low and dependent on location, herbicide, and seed mixture but effects were variable and subtle. Both herbicides reduced larkspur and other broadleaf species. Picloram may be more effective for reducing larkspur and result in less damage to non-target broadleaf plants than 2,4-D. However, picloram might result in a slight reduction in seedling density of seeded forbs. Canopy cover and larkspur density from year 2 after treatment will be presented along with the Geyer's larkspur total alkaloid concentration.