Skip to main content
Advanced Search

Filters: Tags: Allen Press and Society for Range Management (X)

26 results (161ms)   

View Results as: JSON ATOM CSV
Sediment production and infiltration rates were measured in conjunction with an analysis of burning and grazing treatments in a chained pinyon-juniper study in southeastern Utah. While high natural variability was present among sites, no significant changes in sediment production were detected following our prescribed burning or grazing treatments. Following treatment, however, both the burned and grazed sites exhibited significantly depressed infiltration rates during certain time intervals in comparison to the ?undisturbed, natural? woodland control location. Published in Journal of Range Management, volume 29, issue 1, on pages 83 - 85, in 1976.
Infiltration and sediment data from small-plot studies (325 infiltrometer plots) utilizing high intensity simulated rainfall indicate that areas cleared of pinyon-juniper trees and seeded to grass in southern Utah generally show no consistent decrease or increase in sediment yields or infiltration rates at a given point. Of 14 sites studied, four indicated decreased infiltration rates and two indicated increased infiltration rates during one or more time intervals at specific points on the treated areas; one site had significantly less sediment yield and two sites had significantly higher sediment yields from points on the treated areas. These results nearly parallel those obtained during similar studies of 14 pinyon-juniper...
The influence of soil type, grazing level, and vegetation on infiltration rates were evaluated at the Central Plains Experimental Range near Nunn, Colorado. Total plant material was significantly correlated with infiltration rates on two of the three soil types tested. Heavy grazing significantly decreased infiltration rates on two of the soil types. Grazing influences did not reduce infiltration rates until after 20 minutes of simulated rainfall. Published in Journal of Range Management, volume 26, issue 2, on pages 126 - 129, in 1973.
Recent evidence associates the persistence of invasive plant species with disturbance and fluctuations in distinct forms of mineral N in soils. We conducted soil and hydroponic experiments to investigate the influence of N form and availability on germination and seedling development of 2 invasive annual grasses, cheatgrass (Bromus tectorum) and medusahead (Taeniatherum caput-medusae) and 6 perennial grasses, bluebunch wheatgrass (Pseudoroegneria spicata), crested wheatgrass (Agropyron cristatum x A. desertorum), Sand Hollow and Seaman?s Gulch big squirreltail (Elymus multisetus), and Little Camas and Little Wood bottlebrush squirreltail (E. elymoides ssp. brevifolius and E. elymoides ssp. elymoides, respectively)....
The invasion of halogeton (Halogeton glomeratus) on range lands of the Intermountain West has done much to bring these lands into public attention. Large sums of money have been spent for study and control of this plant. The soluble oxalates in this plant are toxic to livestock when consumed in large quantities over a short period of time. For this reason, a knowledge of the factors which affect the oxalate content is important. Therefore, a study was designed to determine the oxalate content of plants on various soils during different seasons of the year. Published in Journal of Range Management, volume 13, issue 2, on pages 97 - 101, in 1960.
Three levels of vehicle impact (2, 8, 32 trips over the same tracks) were applied on rangelands near Ashland, Mont., using a four-wheel-drive Chevrolet Blazer with mud and snow radial tires. The impacts were applied each month, May to September, on previously unimpacted range. Canopy coverage measurements and ground and aerial photography were used to evaluate the impact effects. In the year of impact, canopy coverage measurements showed increasing damage to the vegetation as the number of trips increased. Damage was greater on very moist to wet soils than on dry soils. Vegetation measurements the year following the impacts did not show carry-over damage to vegetation from the 2 and 8 trip treatments, except for...
Rates and patterns of revegetation were studied during and after construction of the 500 kV Navajo Project Southern Transmission Line at two sites in the Arizona Sonoran Desert from 1972 through 1977. Herbs were reduced temporarily during the construction phase of the study. Perennial herbs did not return in the 5-year post-construction period. Annual herbs invaded immediately after disturbance. In one case annual herb density and diversity was higher after disturbance due to removal of larger woody plants. The tree and shrub community exhibited dynamic changes in cover, diversity, and richness, presumably in response to the climate. However, colonization by new species was not observed during the 5 years of study....
Phenological development of aboveground portions of shadscale and winterfat was observed for 7 years in Curlew Valley, Utah, and graphically related to patterns of precipitation and temperature. The considerable variation in year-to-year phenology should be noted by those taking data in other basic and applied studies. Preset dates for livestock management actions that ignore yearly phenological differences could result, in some years, in the plants being used during phenological states that are susceptible to damage by browsing. Seed set cannot be counted on every year, complicating one of the assumptions of rest-rotation grazing. Published in Journal of Range Management, volume 31, issue 1, on pages 43 - 45, in...
A recently burned area near Wallsburg, Wasatch County, Utah, was sampled to determine if differences existed between the soil algal flora of a burned area and that of an adjacent ecologically similar unburned area. Soil samples were cultured and analyzed to determine presence and relative frequency of living algae. The frequency of visible algal patches present after eight days of culturing was much higher in the unburned soil samples than in the burned samples. Percent relative frequencies and absolute densities of diatoms were also determined. Diatom floras of the two areas were very similar. However, the absolute densities of diatoms were significantly greater in the unburned samples. The major effect of the...
Downy brome (Bromus tectorum L.) is an alien grass that dominates disturbed ground in shrub-steppe ecosystems of the western United States. Responses of downy brome to added nitrogen and water were evaluated using intact soil cores obtained from an old field. Gas exchange data were gathered at the leaf and canopy scales. Stomatal conductance and net photosynthesis rates were greater at the leaf scale than at the canopy scale, decreased with time from germination, and were weakly affected by treatments. Water-use efficiency was weakly related to time from germination and treatments. Biomass was greater in the nitrogen-plus-water (7.4 g) treatment, compared with water (3.6 g), nitrogen (4.5 g), and control (3.3 g)...
Four previously published classifications of infermountain shrub vegetation and a new classificafion based on maximum salt tolerances and water relationships are presented. Maps show that the geographic range of salt desert shrub species far exceeds the distribution of mappable communities in which these shrubs are dominants. Species differ in their capacity to tolerate soil osmotic stress, but variable results from measurements of osmotic stress in 20 different plant communities indicate that additional factors must be important in determining species present in different habitats. Data obtained by the use of a new method of measuring total soil moisture stress in field samples show that the capacity of different...
There has been increasing concern that training on military lands results in excessive soil erosion, ecosystem degradation, and loss of sustainable training resources. Vegetation structure has been shown to play a role in soil surface stabilization by reducing shear stress caused by wind force. A study at the Idaho Army National Guard training facility at Orchard Training Area (OTA), Ida. assessed the effect of simulated M1A2 Abrams battletank maneuvers on grassland plant canopies and soil erodibility. The point-intercept method was used to estimate vertical vegetation structure before and after tracking. A portable wind tunnel was used to measure threshold wind speeds (TWS) associated with different numbers of...
The relationship of pure stands of 6 saltbush species to sodium adsorption ratio, electrical conductivity, and alkalinity are documented. The data gathered were obtained while correlating soils to range sites for National Cooperative Soil Surveys. Soil scientists gathered detailed soil information and obtained lab data. Range conservationists correlated the saltbush species to specific soils and by using lab data made a direct relationship to pure saltbush stands. Species ranked from highest to lowest adaptability to SAR, EC, and pH are: mat saltbush (Atriplex corrugata S. Wats.), mound saltbush (A. obovata Moq.), Castle Valley clover (A. cuneata A. Nels.), sickle saltbush (A. falcata (M.E. Jones) Standl.), shadscale...
The purpose of this study was to evaluate vegetation, soils, infiltration rates, and sediment production as they relate to livestock exclusion, continuous heavy grazing, continuous moderate grazing, and rotation grazing on a homogeneous plant-soil complex. The exclusion of livestock resulted in infiltration rates significantly higher than when the pastures were grazed in any system. No differences were found between heavily and moderately stocked pastures. This was attributed to organic matter additions from forbs that replaced grasses when the area was heavily grazed. The rotation treatment had infiltration rates that were lower than the exclosures or continuous grazing treatments. Sediment production from interrill...
Manipulating stocking rate and duration of grazing is fundamental to range management. It has been claimed that rotation grazing systems will increase stocking capacity of range while maintaining or improving animal gains, range condition, and forage production. To test these claims, we compared continuous, 4-pasture rotationally deferred, and 8-paddock short-duration rotation grazing on mixed-grass range near Cheyenne, Wyo. from 1982 through 1987. Grazing pressures ranged from 19 to 81 steer-days per tonne of forage dry matter produced. Steers were weighed biweekly; forage production, utilization, and botanical composition were estimated by clipping; and basal cover was estimated by inclined point frame. Basal...
Vegetative differences and changes were evaluated over a 6-year period (1999-2004) on adjoining conservatively grazed and grazing-excluded (22 years) shortgrass rangelands in northwestern New Mexico. Autumn total perennial grass and blue grama (Bouteloua gracilis [Willd. ex Kunth] Lag. Griffiths) standing crop did not differ on grazed and grazing-excluded areas when data were averaged across years. There were no long-term differences in vegetation basal cover or composition between the grazed and grazing-excluded areas. Plant community similarity values between the grazed and grazing-excluded areas were 80% and 93% during the first 2 years (1999-2000) and last 2 years (2003-2004) of study, respectively. Climatic...
stract(back to top) Indian ricegrass sown on a sandy soil covering a uranium mine tailings exhibited associative nitrogen fixation (acetylene reduction). Acetylene reduction rates for whole plants varied from 2,100 to 19,500 nm/4 days. Nitrogen fixation was associated with the rhizosheaths. It is suggested that the reclamation of mine tailings in arid climates may be facilitated by stabilizing sandy textured coverings with rhizosheath-forming grasses Published in Journal of Range Management, volume 33, issue 3, on pages 204 - 206, in 1980.
Desert needlegrass (Achnatherum speciosum [Trin. & Rupr.] Barkworth) is potentially a valuable native species for use in restoration seedings in the more arid portions of the Great Basin. Seedlings of desert needlegrass were grown in a greenhouse with 5 different densities of cheatgrass (Bromus tectorum L.). The densities of cheatgrass used in the greenhouse experiments were derived from sampling populations in the field where desert needlegrass is adapted and seedling recruitment is desired. Cheatgrass is known to close sites to the establishment of seedlings of perennial grasses through competition for moisture. The response variable was height of desert needlegrass shoots. Height measurements were taken weekly...
thumbnail
Studies were conducted in the mesquite-desert grassland to assess effects of shade, roots, and litter of mesquite trees on understory vegetation and microenvironmental factors. Elimination of mesquite shade and root action increased foliar cover of understory vegetation in the canopy zone from 19% with intact mesquite to 24%. Replacement of mesquite shade with artificial shade screens further increased understory vegetative cover to 32%. Only forbs responded to elimination of mesquite roots in open areas. Vegetation responses indicated improved soil moisture in the canopy zone with both treatments, but there were no detectable soil moisture differences among treatments during the major part of the growing season....
Community dynamics and dominance on cheatgrass (Bromus tectorum L.) and yellow starthistle (Centaurea solstitialis L.) infested rangeland appear to be influenced by resource acquisition rates and duration of growth. Objectives were to determine the effects of densities, proportions, and soil depth on the growth rate and duration of growth of these species. In 6 field experiments isolated individuals, monocultures (100, 1,000, 10,000 plants m-2), and mixtures (same densities arranged factorially) were grown with unrestricted and restricted (0.2- and 0.5-m) soil depths. Shoot weights were determined on 12-day intervals beginning on day 24 and ending on day 72 for plants grown with restricted soil depth and day 96...


map background search result map search result map Effect of Mesquite Trees on Vegetation and Soils in the Desert Grassland Effect of Mesquite Trees on Vegetation and Soils in the Desert Grassland