The tolerance of fourwing saltbush (Atriplex canescens) and cuneate saltbush (Atriplex cuneata) to the salts in processed oil shale was studied in a greenhouse experiment over an Ece range of 4 to 38 mmho/cm. Growth responses differed, depending on the species and the particular salt or salts in the soil solution. Cuneate saltbush was more salt tolerant than fourwing saltbush, but both species survived and grew at salinities as high as 38 mmho/cm. Because of their high salt tolerance these saltbush species may be very important for use in the rehabilitation of processed oil shale disposal sites.

Plant phenology is described for plant species in galleta grass (Hilaria jamesii)-shadescale (Atriplex confertifolia) and galleta grass-sagebrush (Artemisia tridentata ssp. wyomingensis) associations in Hot Creek and Reveille Valleys of Nevada. Species within both plant associations were separated into early, late, and indiscriminate flowering groups. Duration of the species phenology cycles varied from 72 days for Indian ricegrass (ryzopsis hymenoides) to 209 days for sagebrush. The phenological cycle of individual species varied as much as 62 days in length over a 4-year period. Phenology of species common to both galleta grass-shadscale and galleta grass-sagebrush associations was similar in the same year. Differences in species phenology patterns are speculated to indicate different approaches to plant survival and species proliferation, but no one phenology pattern was obviously superior.

Three exotic grasses potentially useful converting south Texas brush rangeland to permanent pasture were evaluated in 1976 and 1977. Yearling cattle required 16.6, 23.1, and 34.8 kg of forage per kg of gain for coastcross-1 bermudagrass, kleingrass-75, and Bell rhodesgrass, respectively. Cattle gained 0.68, 0.56, and 0.33 kg/head daily grazing these species. They ate (forage disappearing) about 12 kg/head daily regardiess of species, so daily gains directly reflected differences in quality among the forages. Our data suggest that the quality measure most nearly deficient was the factor most limiting animal performance, e.g., correlation between average daily gain and P content was r = 0.89 for cattle grazing Bell rhodesgrass. Its P content varied from 0.16 to 0.06% from spring to fall compared to 0.24 to 0.15% from spring to fall for the other two forages. Overall, 24-hr IVDMD (fermentation only) best correlated with animal daily gain. Generally, Bell rhodegrass had lowest, coastcross-1 bermudagrass highest, and kleingrass-75 intermediate quality values, particularly for digestibility, crude protein, and digestible energy. Dry matter yields were 9.6, 11.6, and 11.8 thousand kg/ha for coastcross-1 bermudagrass, kleingrass-75, and Bell rhodesgrass in 1976.

Ecological and historical data are combined in assessing the influence of cultural broadcast burning in the inland Pacific Northwest from the distant past into recent history. Twenty-four references to broadcast burning by native peoples were found in the journals of early explorers and settlers. Broadcast burning was apparently an ancient native tradition, derived from the earliest hunting cultures to enter the region. With the influx of European culture, misapprehensions about fire among whites disrupted the original influence of native cultural burning. Early irresponsible burning became associated with the deterioration of natural resources, and efforts to prevent or suppress all fires were incorporated in developing conservation policies. The reduction of burning, combined with markedly intensified grazing by European livestock, distorted the basic character of existing ecosystems and altered native plant communities. Early photographs of rangelands in east-central Oregon were gathered; their dates range from 1880 to the early 1930's. Photo-sites were re-photographed in 1976. Photoset comparisons show expansions of western juniper (Juniperus occidentalis) populations into adjacent rangeland ecosystems.

A factorial experiment was designed to evaluate the effects of planting depth, number of seeds per seed spot, and the addition of fungicide and/or vermiculite on the emergence of bitterbrush planted on land disturbed by phosphate mining. Optimum emergence occurred from the 1.3 cm (0.5 in) planting depth. Less emergence was noted from plots of 20 seeds per seed spot than from plots with 1, 5, or 10 seeds per seed spot. The data indicate seedling emergence was enhanced with the addition of fungicide and vermiculite.

Various combinations of atrazine, 2,4-D, and NPK fertilizer were applied initially in 1975 on a tallgrass prairie in good condition and again as a retreatment in 1976 on one-half of each treated area. Application of atrazine with fertilizer increased crude protein content, crude protein yield, and range condition during the summer. Differences in protein levels in dormant forage were not evident. Therefore the application of atrazine and fertilizer appears to be more feasible for summer grazing or production of high quality prairie hay than for yearlong or winter grazing.

A study was conducted to evaluate standing crop of forage and cattle diets for a 7-pasture high-intensity low-frequency (HILF) grazing system, and a 7-pasture short-duration grazing (SDG) system on the same area. A 4-pasture, 3-herd (Merrill) deferred rotation grazing system was sampled as a standard for comparison. Standing crop of forage was highest for the HILF grazing system compared to the SDG and Merrill grazing systems. The Merrill system with brush control (Pasture 10) had a greater standing crop than the Merrill system without brush control (Pasture 16) or the SDG system. Standing crop in Pasture 16 was comparable to the SDG system. Cattle diets from the HILF system varied significantly between collections at the beginning and end of each grazing period. A significantly higher percentage of forbs were consumed at the beginning of each grazing period (Period A) compared to the end (Period B). Cattle selected the greatest amounts of pricklypear at the end of each collection period during fall and spring, but not during the winter. Greater amounts of pricklypear were selected when mature grasses and oak and juniper browse were the primary alternatives. Crude protein (CP) levels of diets from the HILF system decreased with shifts in forage selection from Texas wintergrass and forbs (Period A) to pricklypear and dry grass (Period B). Diets from the SDG system were characterized by higher percentages of grass and less forbs and pricklypear compared to the HILF grazing system. Also, there were no major shifts in forage selection between collection period A and B for the SDG system. This resulted in a non-significant difference in CP values for diets collected in period A compared to period B. However, a significant decline was recorded for digestibility of diets between the two collection periods. CP and digestibility were higher for diets from the SDG system compared to the HILF grazing system. Botanical composition and diet quality were comparable for the SDG and Merrill grazing systems. Competition between different kinds of animals may be reduced by changing management from a HILF to a SDG system. This would be important where combinations of animals such as cattle, sheep, goats, and deer utilize a common range. Based on diet quality, livestock production from a SDG system should be equivalent to a Merrill system.

At the Archer Substation near Cheyenne, Wyo., the leaves and flowers of the sandlily (Leucocrinum montanum) were collected separately between May 17 and 22 in 1976, 1977, and 1978 and their crude protein and mineral concentrations were determined. Average crude protein contents of leaves and flowers were 22.1 and 12.4%, respectively. The large difference in protein levels between the flowers and leaves may be a factor in the selective grazing of these parts by livestock. The mineral concentrations of Ca, Cu, Fe, K, Mg, Mn, Na, P, and Zn in flowers and leaves were adequate for livestock nutrition and did not differ greatly except the Ca and K contents of leaves were higher than those of flowers.