Esophagerlly flstulated cows were used on forested range in northeastern Oregon to collect diet samples which were then analyzed by the microhlstological technique. Grasses, forbs, and shrubs averaged 61,16,and 23% of the diet, respectively. Composition of diets differed among years and with seasonal advance. Idaho fescue and elk sedge were the most important forage species consumed. Forbs were used heavily in the early part of the grazing season before maturation. Browse comprised as much as 47% of the diet when green grass was unavailable. Cattle were opportunistic grazers and did not limit their selection to grass species. On forested ranges cattle diets varied among grazing periods within each year as well as among years. Knowledge of dietary habits of livestock and game animals is valuable to the range manager in determining if competition exists among different range animals and in balancing livestock and game numbers with available forage. Also, a knowledge of species consumed tells a manager what the key species are and helps explain changes in diet quality and animal performance (Holechek et al. 1981). At present information concerning cattle diets on forested range in eastern Oregon is limited to utilization studies reported by Pickford and Reid (1948), Harris (1954), Miller and Krueger (1976), and Skovlin et al. (1976). Pickford and Harris (1948), Harris (1954), and Skovlin et al. (1976) conducted their research at the Starkey Experimental Range and Forest in northeastern Oregon. Results from all three studies showed that bluebunch wheatgrass (Agropyron spicufum), Idaho fescue (Festuca iduhoensis). prairie junegrass (Koeleriu cristata), elk sedge (Carex geyeri), Sandberg bluegrass (Pea sandbergii). and pinegrass (Calumugrostis rubescens) were the primary forage species considering availability and utilization. Pickford and Reid (1948) reported that grass was the primary forage class consumed by cattle but forbs were readily utilized in June and early July. Shrubs, particularly common snowberry (Symphoricarpos albus), also received heavy use during some periods although shrubs comprised a small amount of the available forage. Harris (1954) observed that over a 9-year period bluebunch wheatgrass was the forage species most heavily used by cattle followed by prairie junegrass, Idaho fescue, elk sedge, and pinegrass. Skovlin et al. (1976) also found that bluebunch wheatgrass was an important forage species. Elk sedge and pinegrass, however, contributed the most forage. In all three of the previously discussed investigations, Sandberg bluegrass (Poa sandbergii) was one of the most common forage species present but utilization Authors were, respectively, graduate research assistant: associate professor rangeland msources,

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Table 1. Streambank erosion observation periods and treatment identification. Streambank erosional patterns have been studied for 3 years (1 year of calibration and 2 years of active grazing treatment) on the Starkey Experimental Forest and Range in the Blue Mountains of northeastern Oregon. Livestock grazing use at the rate of 3.2 ha/AUM (8 acres/AUM) has not accelerated streambank degradation on Meadow Creek. Most erosion occurred during wintering periods and this erosion has been independent of grazing season treatments. It appears that high runoff and occasional ice flows are the most significant factors in bank cutting on this stream. Literature Cited Hayes, F.A. 1978. Streambank stability and meadow condition in relation to livestock grazing in mountain meadows of central Idaho. M.S. Thesis. Univ. of Idaho. Moscow, Id_91 p.

There is empirical evidence that persistent herbivory by large mammals caused moderate to severe reduction of shrubs and forage productivity in a variety of logged and unlogged forest communities, with subsequent effects on frequency of wildfire and conifer seedling establishment in some plant communities. Long-term herbivory was shown to have alternative effects by either improving or reducing wood-fiber production by reducing competition from understory plants or reducing soil fertility. The changes in plant communities caused by the herbivores may have had negative feedback effects to productivity of both elk and cattle. Cattle do not achieve desired weight gains on summer allotments. Empirical studies on forage quality and livestock nutritional status support a view that large domestic and wild mammals subsist on suboptimal forage conditions most of the year in the Blue Mountains. Survival of elk calves appears low, partly as a result of density-induced shortages of high-quality forage. The reduced calf production appears to be exacerbated by low adult bull:cow elk ratios, which reduces calf survival via delayed and lengthy birthing periods. The low bull:cow ratios are a result of reduced cover due to logging and increased access to hunters due to logging roads. Reduced big game productivity has led to restrictions on hunting opportunities, with concomitant losses in revenue to local economies. In addition, the dense elk herds, in concert with forest management activities on federal lands, have resulted in increased use by elk on private lands, where they damage crops. The paper identifies adaptive management experiments that could identify options for-clarifying the complex relationships between herbivores, vegetation, and ecosystem processes and identify management options for restoring forest health.

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