• Use of ornamental lilac and honeysuckle phenophases as indicators of rangeland grasshopper development

      Kemp, W. P.; Berry, J. S.; Caprio, J. M. (Society for Range Management, 1991-11-01)
      Comparisons were made between phenological phase dates of 2 common ornamental shrubs, purple common lilac (Syringa vulgaris L.) and Zabeli honeysuckle (Lonicera krolkowii Stapf, var. Zabelii (Rehd. Rehder)), and rangeland grasshopper (composite of 6 common species) development for 3 years at 9 sites throughout Montana. Results indicated that spring hatch (75% instar 1) occurred about 10 days after the begin bloom phase of purple common lilac. Peak occurrence of grasshoppers for instar 2 coincided, on average, with the end bloom phase of Zabeli honeysuckle, whereas peak instar 3 occurred about 10 days later. On average, peak instar 4 preceded the first red berry phase of Zabeli honeysuckle by about 8 days, and 75% adult stage occurred about 14 days after red berries first appeared. Our results provide rangeland managers and ranchers with a simple method for the improved timing of assessment and control of rangeland grasshoppers.
    • Utilization of larkspur by sheep

      Ralphs, M. H.; Bowns, J. E.; Manners, G. D. (Society for Range Management, 1991-11-01)
      Sheep are more resistent to larkspur (Delphinium spp.) poisoning than are cattle, and may be used as a biological tool to graze larkspur prior to cattle turn-in to reduce the risk of cattle poisoning. Sheep utilization of 3 species of larkspur was measured at 3 phenological growth states (vegetative, bud, and flower) at 5 locations. Utilization of waxy larkspur (D. glaucescens Wats), varied among years at Ruby, Mont. Use of duncecap larkspur (D. occidentals. Wats) at Oakley, Ida., was uniformly higher in all 3 growth stages due to closed herding practices. Use of tall larkspur (D. barbeyi Huth) increased as it matured. Trailing sheep through larkspur patches, or bedding them in patches greatly increased trampling of larkspur stalks and utilization of heads and leaves.