• A Tractor-powered Method for Installing Earth Anchors during Fence Construction

      Mueller, Dennis M. (Society for Range Management, 1983-03-01)
      A tractor-powered post-hole digger was adapted to screw earth anchors into the soil to reinforce fence corners. Constructing single-brace corners with earth anchors saved approximately 2-1/2 hours over conventional double-braced corners guyed to a buried object for reinforcement.
    • Blue Grama (Bouteloua gracilis) Response To Fertilization of a Claypan Soil in the Greenhouse

      White, E. M.; Gartner, F. R.; Butterfield, R. (Society for Range Management, 1983-03-01)
      Blue grama, grown in situ on the upper 12 cm of a claypan soil in the greenhouse, had greater growth when minor elements were added with N, P, and K. N fertilized plants produced significantly less forage than NPK-fertilized ones but slightly more than unfertilized plants. Renovation of claypan areas to increase water infiltration may need to be accompanied by fertilization with minor elements, particularly on old landscapes where soil weathering has been intense.
    • Comparison of Techniques Used for Adjusting Biomass Estimates by Double Sampling

      Ahmed, J.; Bonham, C. D.; Laycock, W. A. (Society for Range Management, 1983-03-01)
      This paper compares the ratio and regression estimator procedures for adjusting ocularly estimated plant species biomass in different sizes and shapes of plots. The study was conducted in northeastern Colorado on shortgrass rangeland dominated by blue grama (Bouteloua gracilis). No significant differences were found in clipped plant biomass in 4 quadrat sizes between 0.18 and 0.50 m2 and 2 shapes, circular and angular quadrats. For double sampling, the scatter plots of data strongly indicated a linear relationship through the origin for estimation and clipping. There were no significant differences between the adjusted mean weights by use of regression with and without intercept. The intercept was not significantly different from zero. Interpretation of correlation coefficient and variance of regression estimate with no intercept becomes difficult because the regression is forced through zero. Therefore, it is helpful to use regression with intercept. In the present study, estimates of both green and dry weights by ratio and regression estimation were comparable. Regression estimation is a minimum variance estimation comparable to ratio estimation even when the assumption of homoscedasticity is not true.
    • Control of Grasshoppers on Rangeland in the United States—A Perspective

      Hewitt, G. B.; Onsager, J. A. (Society for Range Management, 1983-03-01)
      The periodical ravages of locusts and grasshoppers have been sufficiently documented through history that it is easy to appreciate the seriousness of such outbreaks. We believe, however, that most people grossly underestimate the forage resources that are destroyed annually by typical "noneconomical" populations of grasshoppers. The western range comprises about 262 million ha, most of which is suitable habitat for grasshoppers. The grasshoppers annually destroy at least 21-23% of available range vegetation. That would represent a loss of about $393 million/year if that vegetation could otherwise be utilized by livestock. Current control measures are not economical on about 80 million ha because treatment cost far exceeds the value of forage that is produced. Most control programs are likely to be executed on about 160 million ha that produce forage worth about $2.50 - $7.50/ha. Significant forage destruction begins during the 3rd nymphal instar. This occurs just before maturation of many important species of grass. Thus, grasshoppers do not generally inhibit forage production; rather, they hasten decomposition of the standing crop of forage. When control measures become necessary, they should be initiated as soon as possible after the majority of grasshoppers become 3rd instars. Later treatments cannot recover forage that has already been destroyed; they simply prevent further destruction.
    • Controlling Mature Ash Juniper in Texas with Crown Fires

      Bryant, F. C.; Launchbaugh, G. K.; Koerth, B. H. (Society for Range Management, 1983-03-01)
      Dozed plots and windrow plots were evaluated during 1979 and 1980 with respect to their effectiveness in igniting a crown fire in an adjacent live juniper stand. Dozed plots were ineffective in igniting a crown fire. However, if herbaceous fuel is less than 500 kg/ha, windspeed is less than 10 km/hr, humidity is above 45% and air temperature is less than 30 degrees C, recently chained or dozed juniper (<100 days since treatment) can be burned with minimal risks. Windrowed plots produced the best results for igniting the adjacent crowns. Correlation coefficients and coefficients of determination indicated that air temperature, maximum windspeed, and leaf moisture would best predict the area the fire would burn per 6 m of windrow length. Crown fires usually stopped where distance between trees exceeded 7 to 10 m. For optimum results, average windspeed should exceed 16 km/hr, canopy cover should exceed 35%, relative humidity should be between 20 and 40%, air temperature should be between 2 and 32 degrees C, and leaf moisture should be below 60%. Although potential for broad application is limited, this technique could reduce the total cost of juniper control or could be used in wildlife habitat management.
    • Drought Effects on Diet and Weight Gains of Yearling Heifers in Northeastern Oregon

      Holechek, J. L.; Vavra, M. (Society for Range Management, 1983-03-01)
      Daily weight gains and diets of cattle were evaluated during a year with average precipitation and in a drought year on mountain range in northeastern Oregon. Forage intake was evaluated only in the drought year. Esophageally fistulated heifers were used to sample diet quality and botanical composition. Botanical composition of cattle diets was different (P<.05) in the late spring and early summer between years. When green grass and forbs were not available, browse was heavily utilized. Livestock weight gains and forage intake in the latter part of the grazing season were reduced (P<.05) during the drought year. This is attributed to depletion of browse, primarily common snowberry (Symphoricarpos albus). Diet crude protein and neutral detergent fiber concentrations were significantly (P<.05) correlated with average daily gains. When ruminants are consuming diets with more than one forage class, neutral detergent fiber and composition and yield of volatile fatty acids may more accurately evaluate the energy status of the diet than digestibility. Supplementation of crude protein could potentially improve average daily gains during drought years if browse was unavailable. Ranges with a high component of forbs and shrubs will ameliorate the negative effects of drought on average daily gains.
    • Effects of Cattle and Deer on Regenerating Mixed Conifer Clearcuts

      Kosco, B. H.; Bartolome, J. W. (Society for Range Management, 1983-03-01)
      Study began in 1977 at Blodgett Forest Research Station near Georgetown, California, to look at the effects of cattle and deer grazing on mixed conifer plantations. Cattle graze the study area from June 1 until about September 20 each year. Deer are primarily migratory, passing through the study area in March and April and again in October and November each year. The results of treatments on two clearcuts indicate cattle do not harm tree regeneration. Browsing on trees occurred, but no significantly higher numbers of trees were browsed by cattle and deer than by deer alone. White fir seedlings were browsed the most heavily. No trampling damage occurred. Browsing has made no difference in overall tree seedling height or basal diameter between treatments. Brush cover was significantly reduced on grazed treatments on both clearcuts. On 641E, cattle and deer grazing together made a further significant reduction in brush cover over deer grazing alone. The reduction in brush cover has had no effect on tree seedling heights or basal diameters yet. Tree height, basal diameter, and browsing and trampling damage will continue to be monitored, as will brush cover and species composition. Results from this study indicate however, that proper cattle grazing does not harm tree regeneration on young mixed conifer plantations and furthermore cattle grazing may be used as a vegetation management tool in reducing brush on these clearcuts.
    • Elk Use of Winter Range as Affected by Cattle Grazing, Fertilizing, and Burning in Southeastern Washington Forage Allocation

      Skovlin, J. M.; Edgerton, P. J.; McConnell, B. R. (Society for Range Management, 1983-03-01)
      A study of ways to increase winter use by elk of Pacific bunchgrass foothill range in southeastern Washington employed fertilizing and rangeland burning, with and without spring cattle grazing. First-year response of elk to fertilizer applied in fall (56 kg N/ha) was a 49% increase in use; however, no significant carry-over effect was noted in subsequent years. Fall burning to remove dead standing litter and enhance forage palatability provided no increase in elk use in winter. Intensive cattle grazing in spring to promote regrowth did not increase elk use. In fact, cattle grazing decreased winter elk use by 28% in 1 of the 3 years studied. The cost effectiveness of increasing elk use by fertilizing appeared marginal except perhaps in special situations. A discussion of forage allocation to both elk and cattle is presented.
    • Estimation of Plant Biomass by Spectral Reflectance in an East African Grassland

      Boutton, T. W.; Tieszen, L. L. (Society for Range Management, 1983-03-01)
      Canopy spectral reflectance measurements at 0.800 and 0.675 μm were made in a grassland in Masai Mara Game Reserve, Kenya. The reflectance ratio (0.800/0.675 μm) was shown to be a reliable predictor of green biomass, accounting for 70% of the variance in green biomass values. Significant error in the biomass estimates was shown to be due to plots which contained less than 30% of the total vegetation in the live condition. Estimation error tended to increase when time of sampling departed from the interval of 1000 to 1400 hours, although this trend was not statistically significant. We conclude that the spectral reflectance technique can provide reliable estimates of plant biomass in grassland ecosystems where the proportion of live:total vegetation exceeds 30%.
    • Germination Characteristics of Two Varieties of Kochia prostrata (L.) Schrad.

      Waller, S. S.; Britton, C. M.; Schmidt, D. K.; Stubbendieck, J.; Sneva, F. A. (Society for Range Management, 1983-03-01)
      Kochia prostrata (L.) Schrad. (prostrate summer cypress) is a perennial, half-shrub native to the arid and semiarid regions of Russia, central Europe, and the eastern Mediterranean. It is drought resistant, salt tolerant, winterhardy forage which is desirable for big game browse. K. prostrata has potential for revegetating critical areas on western rangelands. Since limited research has been reported on germination characteristics, the effects of harvest date, seed drying procedures, length of storage, and storage temperature on germination were evaluated for K. prostrata var. virescens and var. canescens. Seed was collected from nursery plots at the Squaw Butte Station, Burns, Ore., on 6 harvest dates (September 20 to November 9, 1978). Seed was aid-dried or dried at 30 degrees C for 24 hours and one seed lot was germinated immediately, while 3 seed lots were stored for 3 months at -18, 4, or 21 degrees C prior to germination trials. K. prostrata var. canescens consistently exhibited higher (p<.05) germination percentages than var. virescens. The effect of harvest date was also significant (p<.05) as both varieties exhibited higher average germination percentage at later harvest dates. Apparently, seeds of either variety did not fully mature until approximately October 20 during the 1978 growing season. Drying procedure affected germination only when seeds were stored for 3 months. Under these conditions air-dried seed had a higher (p<.05) average germination than dried (44.5 and 38.3%, respectively). Higher (p<.05) germination occurred following 3 months of storage at 4 degrees C for both varieties (69.4 and 37.9% for var. canescens and virescens, respectively). K. prostrata var. canescens collected on November 9, 1978, air-dried and stored for 3 months at 4 degrees C had the highest germination (97%).
    • Habitat Use of Feral Horses and Cattle in Wyoming’s Red Desert

      Miller, R. (Society for Range Management, 1983-03-01)
      Habitat selection by feral horses (Equus caballus) and cattle (Bos taurus) was studied with a series of 16 flights, between November 1977 and April 1979, during which the locations of cattle and feral horses were mapped. The C7 coefficient of association and percent occurrence in different vegetation types and near water sources and ridges were used to compare and describe the habitat use patterns. Cattle and feral horses showed seasonal patterns relative to vegetation types and distance from water sources, and horses showed a seasonal use pattern in regard to areas near ridges. Possibilities for direct competition between cattle and feral horses in the Red Desert were strongest for forage during the fall and in severe winters, and for water during the summer.
    • Herbicide Treatment and Vegetation Response to Treatment of Mesquites in Southern New Mexico

      Herbel, C. H.; Gould, W. L.; Leifeste, W. F.; Gibbens, R. P. (Society for Range Management, 1983-03-01)
      Mesquite (Prosopis juliflora) is a major unwanted plant in the Southwest. This study evaluated the herbage responses obtained from various aerial applications of 2,4,5-T on mesquites in southern New Mexico. The dead plants on the various areas ranged from 7-64% of the mesquite. Yields of perennial grasses ranged from 3-1931 kg/ha on the untreated controls and 11-2696 kg/ha on the areas sprayed with 2,4,5-T. In dense stands of mesquite, about 30% of the mesquites must be killed before grass yields are significantly increased.
    • Impact of Range Goats on Infiltration Rates in Southwestern Utah

      Gifford, G. F.; Provenza, F. D.; Malechek, J. C. (Society for Range Management, 1983-03-01)
      Three levels of goat browsing on a blackbrush site in southwestern Utah had no significant impact on infiltration rates. The probable reason for these results was the presence of a vesicular soil crust, which is unstable when wet and therefore masks any browsing impacts.
    • Infiltration Rates and Sediment Production Following Herbicide/Fire Brush Treatments

      Knight, R. W.; Blackburn, W. H.; Scifres, C. J. (Society for Range Management, 1983-03-01)
      Terminal infiltration rates were similar in soils on which a heavy whitebrush (Aloysia lycioides) cover had been aerially treated with 2 kg/ha (active ingredient) of 20% tebuthiuron pellets 4 years previously or on tebuthiuron-treated plots which had been prescribed burned the winter about 9 months prior to infiltration measurements, compared to untreated sites. However, sediment production was greater from plots treated with the herbicide than from areas subjected to the herbicide-fire system or from untreated plots. Only minor variations in infiltration rates occurred among sites originally dominated by running mesquite (Prosopis reptans) which were aerially sprayed with 2,4,5-T + picloram (1:1) at 1.1 kg/ha 3.5 years previously, burned 10 months previously, subjected to the herbicide-fire system or left untreated. However, sediment production on the running mesquite areas which had been sprayed tended to be greater than on untreated plots. Sediment production on areas subjected to the herbicide-prescribed burning system tended to be less than from brush-covered plots. Differences in sediment production in both experiments were generally attributed to slightly reduced mulch loads and mulch covers where the brush was removed as a leaf mulch donor by herbicide treatment. Prescribed burning apparently compensated for loss of brush leaf mulch by promoting grass cover on herbicide-treated areas.
    • Influence of spring burning on cattle diets and performance on the Edwards Plateau Rangeland

      McGinty, A.; Smeins, F. E.; Merrill, L. B. (Society for Range Management, 1983-03-01)
      Immediately following spring burning of Edwards Plateau rangeland, steer diets had a higher percentage of grass and lower percentage of forbs than diets from unburned range. Intake of pricklypear cactus was greater on burned range than on unburned during the first summer and fall following the fire. Ash content of steer diets in the burn was generally higher, due primarily to increased use of pricklypear cactus on burned sites. Steer diets from burned range contained significantly higher in vitro digestible organic matter (IVDOM) during June. Increased use of pricklypear cactus contributed to a significantly higher IVDOM during September and October and lower percent crude protein from September to November in the burn. Heifers gained significantly more on burned range during June and August and also when averaged across the entire 5-month grazing period. Burning has potential as a useful tool to increase cattle production from Edwards Plateau rangeland.
    • Microclimate Modification of Tall Moist Grasslands of Natal by Spring Burning

      Savage, M. J.; Vermeulen, K. (Society for Range Management, 1983-03-01)
      The purpose of this study was to investigate modifying microclimatic effects of spring burning in tall grassland, long-term burning trials at Ukulinga, Pietermaritzburg, South Africa. Soil temperature (at 50 mm), soil heat, net radiation and surface reflection coefficient were monitored on various cloudless days before and after burning. Four days after burning there was no significant increase in soil temperature but soil heat and net radiation increases and surface reflection coefficient decreases (from 15% to nearly 3% at local noon) were evident. Between burning date and first day of measurements, a rainfall of less than 2 mm occurred causing greater evaporation at the burnt site (due to greater net radiation) and hence lower soil temperatures, compared to the control site. Burning also resulted in an increase in sensible plus latent plus photosynthetic heat densities (from a daily total density of 9.0 MJ m-2 before to 9.9 MJ m-2 after burning) with soil heat density increasing by 50%. Four weeks after, soil temperature and soil heat were greater for the burnt site compared to the control, but net radiation and surface reflection coefficient were not significantly different between the two sites. The appearance of green material some short time after burning is therefore probably a result of more favourable soil-plant water and surface energy relations.
    • Mitigation of Chaining Impacts to Archaeological Sites

      Haase, W. R. (Society for Range Management, 1983-03-01)
      Current strategies for protecting archaeological sites during implementation of brush management practices such as chaining are frequently inadequate. Potentially significant prehistoric remains are sometimes dealt with in a fashion conducive to their destruction. This conflict can be alleviated by developing a chaining program in which there is planned avoidance of cultural resources. This is accomplished through an intensive archaeological, soil, range, and visual assessment of project areas prior to chaining. The development of a chaining design by an interdisciplinary planning team and the "buffering" of sites during implementation of the range improvement can enhance all resources. Through careful planning, secondary impacts such as vandalism to prehistoric sites can be reduced as well.
    • Multivariate Statistical Methods to Determine Changes in Botanical Composition Vegetation

      Stroup, W. W.; Stubbendieck, J. (Society for Range Management, 1983-03-01)
      Confusion exists over the proper statistical methodology to use in analyzing the effect of treatments on changes in botanical composition over time. A rationale for using multivariate statistics is presented. Basic considerations involved in the use and interpretation of multivariate statistics specifically appropriate to the botanical composition problem are given. An example of how such an analysis can be performed using a common statistical computing package (SAS) is demonstrated.
    • Nutritional Value of Crested Wheatgrass for Wintering Mule Deer

      Urness, P. J.; Austin, D. D.; Fierro, L. C. (Society for Range Management, 1983-03-01)
      The nutritional value of crested wheatgrass in the fall to spring diet of mule deer was determined from in vivo and in vitro digestibilities, a field grazing trial, and crude protein analyses. Its dietary significance was evaluated by comparing the known diet with and without the grass component. Findings indicated fall regrowth and spring growth of crested wheatgrass favorably affected the nutritional plane of mule deer on winter range dominated by big sagebrush having intermingled seedings of this exotic grass.