• Using Aerial Photography for Detecting Blackbrush (Acacia Rigidula) on South Texas Rangelands

      Everitt, J. H. (Society for Range Management, 1985-05-01)
      Blackbrush (Acacia rigidula) is a native shrub found on a variety of soil types in south Texas and northern Mexico. It often becomes a serious management problem on rangelands, especially where associated species have been removed. During late February to late March it produces small cream to light yellow flowers that encompass the entire plant giving it a conspicuous appearance. Field spectroradiometric plant canopy measurements showed that blackbrush in flower had significantly higher (p=0.05) visible light (0.45- to 75-um waveband [WB) reflectance that did 6 other associated plant species or mixtures of species. The conspicuous light yellow color of blackbrush in flower made it distinguishable from other plant species on both conventional color (0.40- to 0.70-um WB) and color-infrared (CIR) (0.50- to 0.90-um WB) aerial photos. However, conventional color photography was superior to CIR photography because blackbrush had a more distinct image on color photography and it could also be identified on smaller scale photos. Microdensitometric measurements made on conventional color film showed that blackbrush had significantly lower optical counts than those of associated species. These results show that aerial photography may be a useful tool to distinguish blackbrush from other plant species in late winter or early spring to locate its endemic areas, monitor its spread, and delineate areas needing control.
    • Topsoil and Mulch Effects on Plant Species and Community Responses of Revegetated Mined Land

      Pinchak, B. A.; Schuman, G. E.; Depuit, E. J. (Society for Range Management, 1985-05-01)
      Replacement of topsoil and the use of mulches for soil stabilization have become important components of mined land reclamation plans in the western United States. Four topsoil depths (0, 20, 40, and 60 cm) and 2 mulch methods [crimped straw and standing barley (Hordeum vulgare L. Otis) stubble] were investigated on uranium mined land in Wyoming. Although 20 cm of topsoil provided initial benefits to stand establishment, after 4 growing seasons, 40 cm of topsoil was required to improve seeded grass growth over that found in non-topsoiled plots. Forty centimeters of topsoil was also found to result in the lowest biomass of invading annual and biennial forbs (nonseeded species). Barley stubble mulch resulted in significantly (P = 0.05) higher biomass of seeded grass species than did crimped straw mulch when at least 40 cm of topsoil was present.
    • The Effect of Early Winter or Spring Burning on Runoff, Sediment, and Vegetation in the Post Oak Savannah of Texas

      Garza, N. E.; Blackburn, W. H. (Society for Range Management, 1985-05-01)
      A replicated small plot (1.8 m × 22.1 m) study was conducted on the Texas A&M University Native Plant and Animal Conservancy in Brazos County, Texas. The purposes of the study were to determine the effects of seasonal burning on runoff and sediment loss and to describe vegetal differences resulting from the burning treatments. A grass-dominated community and a brush-dominated community were studied. Mean runoff from both communities tended to be greater from unburned plots than from burned plots although differences were seldom significant. Mean sediment export (kg/ha) was similar from the treatments during the 15-month study. However, nonsignificant trends suggested that plots burned in the spring lost less sediment than did unburned plots or those burned in early winter. Most sediment loss occurred during June, September, and November as a result of highly intense thunderstorms. Burning did not adversely affect runoff or sediment. Changes in vegetative composition and vigor did occur and these changes appeared to be compatible with most management objectives. Percent foliar cover of live vegetation was greater on burned than unburned plots; however, total foliar cover was greatest on unburned plots. Burning in early winter favored growth of forbs, whereas spring burning tended to favor the production of grasses.
    • Technical Notes: A Floating Quadrat

      Tanner, G. W.; Drummond, M. E. (Society for Range Management, 1985-05-01)
      A clipping quadrat of PVC pipe was constructed to sample emergent phytomass in freshwater marshes. This apparatus is light and durable, and most importantly, has the ability to float. It can be constructed to meet most commonly used quadrat sizes with the ability to be assembled and dismantled in the field for ease of transportation. Terrestrial applications for this type of quadrat also are possible.
    • Stubble Height, Basal Cover, and Herbage Production Relationships in Grasslands of Northern Greece

      Papanastasis, V. P. (Society for Range Management, 1985-05-01)
      Leaving an amount of mulch at the end of the grazing period, before the new growing season starts is vital in maintaining productivity in grasslands on a sustained yield basis. Mulch was expressed as stubble height at 6 levels (0, 3, 6, 9, 12, and 15 cm) and was related to basal cover and herbage production attained at the end of the growing season for 5 consecutive years. The research was conducted on 3 perennial grassland sites with a Mediterranean-type climate, representing the low, middle, and high (subalpine) ecological zones in northern Greece. Bare soil was significantly increased with nearly all stubble heights as compared to the control while mulch cover had an opposite response. There were significant changes in the absolute cover of the dominant species, especially perennial bunchgrasses, but the overall grass and forb cover was not significantly affected. Stubble heights of 12 or 15 cm at the low site and 6 to 15 cm at the other two sites produced the highest yields. These were not significantly different from the control, indicating that the middle and the high sites can withstand closer grazing than the low site.
    • Seasonal Changes in Nitrogen and Moisture Content of Cattle Manure in Cool-Season Pastures

      Lysyk, T. J.; Easton, E. R.; Evenson, P. D. (Society for Range Management, 1985-05-01)
      Fresh cattle manure was collected weekly from 3 cool-season riparian pastures in southeastern South Dakota during the summer of 1981 to determine the relationship of diet of livestock to manure quality. Five manure samples collected from each site were returned to the laboratory, mixed thoroughly, and subsampled to determine the percent moisture and percent total nitrogen of the feces. Moisture content of the manure was highest during the month of June but decreased later in the summer. Nitrogen content was highest in late spring and declined in July with a rise noted again in August. Nitrogen content appeared to follow reported changes in forage quality, particularly in vitro digestibility.
    • Screening Range Grasses for Resistance to Black Grass Bugs Labops hesperius and Irbisia pacifica (Hemiptera: Miridae)

      Hansen, J. D.; Asay, K. H.; Nielson, D. C. (Society for Range Management, 1985-05-01)
      Resistance to feeding by black grass bugs (Hemiptera: Miridae), Labops hesperius Uhler and Irbisia pacifica (Uhler), was studied in 5 range grasses: 3 crested wheatgrass [Agropyron cristatum (L.) Gaertn., A. desertorum (Fisch. ex Link) Schult., and the A. cristatum × A. desertorum hybrid], and 2 hybrids between quackgrass [Elytrigia repens (L.) Nevski] and bluebunch wheatgrass [Pseudoroegneria spicata (Pursh) Löve]. The grasses were screened as seedlings in 4 trials with caged insects. Based on the amount of damage, the crested wheatgrass hybrid was the most susceptible and the other hybrids the most resistant. Resistant individuals were also identified within each grass population. No differences were found in feeding preferences of the 2 black grass bug species. Clones of crested wheatgrass previously selected as individual seedlings maintained their resistance in subsequent replicated trials.
    • Rhizomes and Roots Below Clipped Pinegrass Tillers Have a Higher Percent Carbohydrate when Attached to Other Nonclipped Tillers

      Stout, D. G.; Brooke, B. (Society for Range Management, 1985-05-01)
      Percent total nonstructural carbohydrate (TNC) was measured in rhizomes plus roots of pinegrass (Calamagrostis rubescens Buckl.). The influence of connecting rhizomes on % TNC was evaluated by comparing results from sods with severed rhizomes to results from sods with intact rhizome connections. Severing rhizomes had no effect on % TNC of rhizomes plus roots of nonclipped sods. However, for clipped sods, % TNC was lower if rhizomes had been severed. Presumably, when rhizome connections are left intact, surrounding nonclipped tillers translocate carbohydrates to rhizomes plus roots of clipped tillers within a sod. This result has important implications in the grazing resistance of pinegrass. Since grazing typically involves an uneven utilization of a grass stand, the ungrazed or lightly grazed tillers should play an important role in maintaining the overall vigor of a pinegrass stand.
    • Predicting Yield Response to Nitrogen Fertilization on Northern Great Plains Rangelands

      Wight, J. R.; Godfrey, E. B. (Society for Range Management, 1985-05-01)
      Using a data base developed from range fertilization research results in the Northern Great Plains, yield-predicting equations for both fertilized and nonfertilized range (r2=0.83; n = 194 and r2=0.88; n = 51, respectively) were developed. Independent variables included combinations of monthly precipitation and average site yield for nonfertilized range and additional variables representing N-rate, N-sink effect, and N-rate with precipitation interactions for the fertilized range. Average site yield provided an effective means of accounting for the wide range of inherent productivity among range sites. The results of this research indicated that, in the Northern Great Plains, yield response of native range to N fertilization can be reliably predicted using readily obtainable climatic and site data.
    • Nest Site Selection by Mountain Plovers in Northcentral Montana

      Olson, S. L.; Edge, D. (Society for Range Management, 1985-05-01)
      Nest site selection of the mountain plover (Charadrius montanus) was studied on the Charles M. Russell National Wildlife Refuge, Montana, during 1982. Vegetative characteristics of 26 nest sites, all on prairie dog towns, were compared to a random sample of plots on prairie dog towns and adjacent areas. Total plant cover, grass cover, big sagebrush (Artemisia tridentata) and prickly pear (Opuntia polyacantha) density, and mean vegetation height were all significantly greater (P<0.05) in areas adjacent to prairie dog towns than at the nest sites; litter cover and fringed sagewort (Artemisia frigida) density were greater at the nest site. Within prairie dog towns, erosion pavement cover and mean vegetation height were greater on randomly sampled plots than at the nest sites. Mountain plovers select nest sites on prairie dog towns in patches of greater cover and less vegetative height than occur at random sites within the towns. Prairie dog towns offer islands of suitable mountain plover habitat and should be maintained on the Refuge, especially in light of the prairie dog control programs conducted on adjacent lands.
    • Intake and Diet Selection by Protein Supplemented Grazing Steers

      Judkins, M. B.; Krysl, L. J.; Wallace, J. D.; Galyean, M. L.; Jones, K. D.; Parker, E. E. (Society for Range Management, 1985-05-01)
      Nine esophageal-fistulated and 12 rumen-cannulated steers were randomly allotted to 3 equal supplement groups: cottonseed cake (CSC), ground, pelleted alfalfa hay (ALF), or no supplement (CON). Supplements were individually fed at isonitrogenous levels (1.7 kg hd-1 CSC vs. 3.5 kg hd-1 ALF) every other day. Animals were maintained on treatment from January through April 1983 while grazing blue grama (Bouteloua gracilis) rangeland in southcentral New Mexico. Esophageal samples were collected at 2 times during this period: early February and late March; intake was estimated from total fecal collections in late February and early April. Esophageal samples were analyzed in the laboratory for nitrogen (N) components, in vitro digestibility, fiber, and botanical composition. Animal selection for total grass content of the diet was not influenced (P>.10) by supplementation but declined from February to March (31.8% vs. 21.2%, respectively). Blue grama and mat muhly (Muhlenbergia richardsonii) comprised over 66% of the grass component. Total forbs selected was not influenced by supplementation but increased (P<.05) from February (68.2%) to late March (78.8%), which may be the result of declining quantities of grass and emergence of forbs because of spring moisture. Dietary N components were not affected by supplementation. Soluble N, insoluble unavailable N, and crude protein were higher (P<.05) in February than March as a result of increasing forb consumption and possible N leaching from grass. Fiber components, acid detergent fiber and acid detergent lignin, as well as organic matter digestibility of the diet, were not influenced by supplementation, and increased from February to March but only organic matter digestibility was higher (P<.05) in late March than in early February. Forage organic matter intake was not influenced by supplementation (P>.49), type of supplement consumed, or sampling period (P>.90). Total organic matter intake however, differed (P<.05) between treatment groups because of addition of supplements. Results of this study indicate protein supplementation of wintering steers does not influence botanical or chemical composition of their diets or amount of forage consumed.
    • Influence of Site Manipulation on Infiltration Rates of a Depleted West Texas Range Site

      Bedunah, D. J.; Sosbee, R. E. (Society for Range Management, 1985-05-01)
      Infiltration rates significantly increased each year of the 3-year study on a deteriorated site heavily infested with mesquite (Prosopis glandulosa). Vibratilling resulted in the highest infiltration rates of all treatments by increasing soil roughness and porosity. Shredding mesquite increased infiltration compared to no treatment. The shredding of mesquite increased the amount of soil cover by increasing litter and standing crop. Removal of mesquite by foliar spraying with 2,4,5-T + picloram, mechanical grubbing, or mechanical grubbing and planting to kleingrass (Panicum coloratum) did not increase infiltration. Plant cover and herbaceous standing crop were the most important factors affecting infiltration for treatments without mechanical soil disturbance. Soil variables such as surface roughness, organic carbon and porosity affected infiltration rates on treatments receiving mechanical disturbance. However, interactions between soil and plant variables were important in controlling infiltration on mechanically disturbed and mechanically undisturbed sites.
    • Green Needlegrass Seedling Morphology in Relation to Planting Depth

      Fulbright, T. E.; Wilson, A. M.; Redente, E. F. (Society for Range Management, 1985-05-01)
      Green needlegrass (Stipa viridula Trin.) is commonly used in range seedings and revegetation of disturbed lands in the northern Great Plains. This study was conducted to determine the influence of planting depth, seed source, and temperature on morphology and emergence of green needlegrass seedlings. Seeds from 2 sources were planted at depths of 1.5, 3.0, 4.5, 6.0, and 7.5 cm in pots filled with sandy loam soil. Pots were placed in growth chambers adjusted for either a 20/15 degrees C (15 h light/9 h dark) temperature regime or a 25/20 degrees C regime. Coleoptile length increased with planting depth, while seminal primary root length, adventitious root length, and number of adventitious roots decreased with planting depth. 'SD-93' seedlings had shorter subcoleoptile internodes, longer coleoptiles, and better root development than 'Lodorm' seedlings. Seedlings grown under the warmer temperature regime had better root development than seedlings grown under the cooler regime, but reach of the coleoptile above planting depth was not as great. Results indicated that green needlegrass generally should not be planted at depths greater than 3.0 cm because of lower percent emergence, rate of emergence, and poor root development when seedlings emerged from greater depths.
    • Germination and Seedling Growth of Tall Wheat-Grass and Basin Wildrye in Relation to Boron

      Roundy, B. A. (Society for Range Management, 1985-05-01)
      Seedling establishment on many saline, arid rangeland soils in the Great Basin may be limited not only by low soil osmotic and matric potentials, but also by high boron concentrations. Germinationa and seedling growth of tall wheatgrass [Agropyron elongatum (Host) Beau. 'Jose'] and basin wildrye (Elymus cincereus Scribn. and Merr. 'Magnar') were measured in relation to increasing boron concentrations in laboratory and greenhouse experiments. Rate and total germination of both species were unaffected by boron concentrations up to 200 ppm, while radicle length was unaffected at less than 100 ppm. Growth of both species was much more sensitive to boron than was germination. Root growth of both species was more sensitive to boron than shoot growth. Shoot growth of Jose tall wheatgrass was less sensitive to boron than that of Magnar basin wildrye. Reduction in root and shoot yield of 50% occurred at soil saturation extract concentrations of 30 and 66 ppm of boron, respectively, for Jose tall wheatgrass, and 22 and 37 ppm of boron, respectively, for Magnar basin wildrye. Boron concentrations ranging up to 97 ppm in the saturation extract of a typical Great Basin saline soil in central Nevada would probably affect seedling growth and survival, but not emergence of these species. The fact that Jose tall wheatgrass has greater absolute root growth and boron tolerance than does Magnar basin wildrye may account, in part, for its greater seedling survival on a saline soil in central Nevada.
    • Forage Responses of Buffelgrass and 'Pretoria 90' Bluestem to Nitrogen and Phosphorus Fertilization in a Subtropical Climate

      Wiedenfeld, R. P.; Woodward, W. T. W.; Hoverson, R. R. (Society for Range Management, 1985-05-01)
      A major land use, especially in drier areas of subtropical regions is for forage production. Nutrient availability, as well as moisture, limit production; however, little is known concerning optimum fertilization practices and how nutrient use interacts with rainfall to affect forage yields. A study was conducted on a sandy upland soil under subtropical conditions to determine the effects of nitrogen (N) and phosphorus (P) fertilization on yield, rainfall use efficiency, nutrient uptake, and apparent fertilizer recovery on improved pastures. Established buffelgrass showed dramatic yield responses to N application, while newly planted Pretoria 90 bluestem showed yield responses to N only after residual nutrients had been depleted. Yield responses to N application were mostly quadratic, showing decreasing benefit from N with increasing N application rate. Smaller yield responses to P occurred in the first 2 years on Pretoria 90 and at higher N application rates on buffelgrass. Rainfall use efficiency (yield per unit of rainfall received) for buffelgrass increased greatly with increasing N application rate. Rainfall use efficiency of newly planted Pretoria 90 increased during each of the first 3 years as the stand developed, but was not greatly affected by N fertilization level. Nutrient contents in both grasses generally increased with increasing nutrient application. Both N and P removal by buffelgrass increased primarily with increasing N application. Apparent N and P fertilizer use efficiency by both grasses was affected very little by rate of application of either nutrient but increased with increasing annual rainfall.
    • Food Habits and Distribution of Cattle on a Forest and Pasture Range in Northern Idaho

      Mitchell, J. E.; Rodgers, R. T. (Society for Range Management, 1985-05-01)
      The food habits and distribution of a cow-calf herd on a northern Idaho summer range was studied for 2 years. The forest-pasture range consisted of comparable areas of seeded grassland (pasture), tall brush, and forest communities. The entire area was classified as Douglas-fir (Pseudotsuga menziesii)/ninebark (Physocarpus malvaceus) habitat-type; however, ponderosa pine (Pinus ponderosa) dominated the forested communities. By early July, up to one-half of the cattle diet came from forest species, primarily browse. Ninebark comprised the major browse diet component. Browse species were selected more frequently in 1978, a wet year, than in the drought year of 1977, primarily because the livestock spent more time in the pasture during 1977. This occurred even though pasture production was much greater in 1978. Range managers in the northern Rockies should consider the forage value of tall shrubs when planning grazing programs.
    • Endomycorrhizae Enhance Growth of Shrub Species in Processed Oil Shale and Disturbed Native Soil

      Call, C. A.; McKell, C. M. (Society for Range Management, 1985-05-01)
      A greenhouse experiment was conducted to determine if the inoculation of native shrubs with vesicular-arbuscular mycorrhizal (VAM) fungi would provide plants better adapted for a minimaltreatment revegetation program for processed oil shale and disturbed native soil. Seedlings of fourwing saltbush {Atriplex canescens (Pursh.) Nutt.}, big sagebrush (Artemisia tridentata Nutt. ssp. wyomingensis), rubber rabbitbrush {Chrysothamnus nauseosus (Pall.) Britton var. nauseosus}, and greasewood {Sarcobatus vermiculatus (Hook.) Torr. var. vermiculatus} were inoculated with Glomus fasciculatum (Thaxter sensu Gerdemann) Gerdemann and Trappe, and Glomus mosseae (Nicol. and Gerd.) Gerdemann and Trappe. Inoculated and noninoculated plants were transplanted into Paraho processed oil shale and disturbed native soil in a containerized system. Plants inoculated with VAM fungi had greater shoot biomass and phosphorus (P) contents than noninoculated plants in both media. Inoculation with VAM fungi had a variable effect on the nitrogen (N) contents of plants in both media. When fertilized with 34 kg/ha N and P, inoculated plants were more effective in taking up applied P than noninoculated plants. Mycorrhizal infection levels were greatly reduced when inoculated plants were grown in processed shale.
    • Effects of Stocking Rate on a Rough Fescue Grassland Vegetation

      Willms, W. D.; Smoliak, S.; Dormaar, J. F. (Society for Range Management, 1985-05-01)
      A study was conducted to examine the effects of 4 stocking rates on the vegetation in a Rough Fescue Grassland vegetation in southwestern Alberta. Stocking at a light rate (1.2 AUM/ha) for 32 years did not affect range condition. However, a modest increase in stocking rate (1.6 AUM/ha) led to a marked decline in range condition. This was associated with a change in the composition of rough fescue from 38 to 21% of basal area. Rough fescue (Festuca scabrella) was nearly eliminated with a stocking rate of 2.4 AUM/ha. Rough fescue was replaced by Parry oat grass (Danthonia parryi) which increased from 24% at 1.2 AUM/ha to 48% at 2.4 AUM/ha. However, stocking at 4.8 AUM/ha resulted in severe deterioration of the grassland. This required annual adjustment of the stocking rate to avoid animal losses. The recommended stocking rate for good condition range in the area is 1.6 AUM/ha. Recovery of the vegetation within the exclosures, from the time of their construction, to a stable range condition, took from 14 years in the lightly grazed field to more than the length of the study in the very heavily grazed field. The duration required for recovery was related to the original range condition of the exclosures.
    • Effect of Sagebrush Control Methods and Seeding on Runoff and Erosion

      Brown, J. C.; Evans, R. A.; Young, J. A. (Society for Range Management, 1985-05-01)
      A large-plot (27 m2) rainfall simulator was used to examine the effects of controlling Wyoming big sagebrush (Artemisia tridentata ssp. wyomingensis) and seeding with crested wheatgrass (Agropyron desertorum) upon infiltration rates and soil erosion in central Nevada. A new parameter-runoff initiation frequency index (an estimate of frequency of occurrence in years that a natural storm will produce surface runoff at the site) was also used for making treatment comparisons. The runoff initiation index reflects a more comprehensive appraisal of hydrologic response on semiarid rangelands than does infiltration rate but sometimes results in a different assessment of treatment effects. Initially, all range improvement techniques reduced terminal infiltration rates and increased sediment yields. The magnitude of treatment effects varied in proportion to the degree of site disturbance: plowing/seeding caused the greatest impact, burning/seeding next, and spraying/seeding had only minimal effect. Treatments showed a steady trend toward recovery in a 2-year period. In terms of runoff initiation frequency, however, plowing/seeding had the least detrimental effect with burning/seeding and spraying/seeding having greater effect. Trends subsequent to treatment indicated watershed improvement of plowed/seeded areas and a decline in burned/seeded areas. These somewhat contradictory results are due to the runoff retention capability of furrows created by plowing and/or artificially seeding across the slope. Surface storage characteristics are incorporated in runoff initiation frequency indexing but not in infiltration rates alone.