• Vegetative Response to Clearcutting and Chopping in a North Florida Flatwoods Forest

      Moore, W. H.; Swindel, B. F.; Terry, W. S. (Society for Range Management, 1982-03-01)
      Selected naturally regenerated flatwoods forests were clearcut and chopped in preparing a large, long-term study of the effects of several multiple-use management practices on forest vegetation and wildlife. Early effects of clearcutting and chopping on understory vegetation are reported here. Clearcutting and chopping reduced woody understory coverage from 66 to 18% of surface area. Common gallberry and saw-palmetto were reduced by 75 and 89%, respectively. Herbaceous species frequency was increased: Panicums by over 3,000%; bluestems by 173%; grasslikes by over 2,000%; and forbs by 308%. Graphical analyses show an increase in herbaceous species diversity as a result of mechanical site disturbance. Comparing these graphs with those reported on the effects of prescribed burning suggests that the collective vegetative response to mechanical site disturbance is qualitatively similar to the response to fire. Quantitatively the response to mechanical disturbance is more pronounced.
    • Using Blue Grama Sod for Range Revegetation

      McGinnies, W. J.; Wilson, A. M. (Society for Range Management, 1982-03-01)
      Blue grama (Bouteloua gracilis) is often difficult to establish by direct seeding, but in many cases it can be established on some critical areas by sodding. Best results were obtained by: (1) transplanting the sod early in the season (May or June), (2) cutting the sod about 5 cm thick and keeping it flat in transit, (3) pre-wetting the sod before cutting if the soil was not already wet, and (4) irrigating the sod immediately after laying and preferably an additional two times during the following week. Establishment depended mainly on development of new adventitious roots which were produced only on recently developed tillers. Sod transplanted in May and June produced the most new adventitious roots; sod transplanted in June and July had the greatest rate of adventitious root elongation; and sod transplanted in June produced the greatest total length of new adventitious roots per sample.
    • The Relative Impact of Various Grasshopper Species on Stipa-Agropyron Mixed Prairie and Fescue Prairie in Southern Alberta

      Hardman, J. M.; Smoliak, S. (Society for Range Management, 1982-03-01)
      Sweep-net samples of grasshoppers were taken annually in late August at Stavely (1970-78) on Festuca scabrella prairie and at Coalhurst (1971-79) on Stipa-Agropyron prairie. Mean catches of grasshoppers were higher (170 vs 112 per 50 sweeps) and more species were sampled (27 vs 13) at Coalhurst. Melanoplus dawsoni (Scudder) was the dominant grasshopper at Stavely while Encoptolophys sordidus costalis (Scudder) and Melanoplus infantilis (Scudder) were codominants at Coalhurst. Grasshoppers were also sampled at two other sites in 1971 and one in 1971 and 1972 on Stipa-Agropyron prairie. Mean catches per 50 sweeps were 122, 164, and 234, respectively, at these sites with 14, 12, and 11 species of grasshoppers sampled. The dominant species were Ageneotettix deorum (Scudder), M. infantilis, and M. dawsoni. Of the 35 species collected at the study sites, 21, those forming at least 1% of the grasshoppers collected at one or more sites, were evaluated for their potential impact on rangeland. Population counts and published data on phenology, damage to rangeland, and feeding preferences were considered. The per capita feeding rate of adults-assumed to be proportional to the 0.68 power of body weight-was also assessed. Using these criteria, all but two species-Melanoplus femurrubrum femurrubrum (DeGeer) and M. dawsoni-were considered potentially damaging. Adult weights varied such that an adult M. infantilis, the smallest species, would feed at 28% the rate of an adult Metator pardalinus (Saussure), the largest species. Published data on habitat preferences of the 21 species show that most of the damaging species prefer sparsely vegetated habitats and thus would be favored where range is overgrazed by cattle.
    • The Nutritional Basis for Food Selection by Ungulates

      Hanley, T. A. (Society for Range Management, 1982-03-01)
      A conceptual framework is outlined for understanding the reasons why ungulates select the kinds of foods that they do. It consists of four morphological parameters: (1) body size and (2) type of digestive system (cecal or ruminant) determine the overall time-energy constraints within which the ungulate may forage selectively; (3) rumino-reticular volume to body weight ratio determines the type of food the ruminant is most efficient in processing; and (4) mouth size determines the ability of the ungulate to harvest selectively plant parts of individuals. Principal premises are the following: (1) large ungulates and cecal digestors are more limited by time than are small ungulates and ruminant digestors; (2) high rumino-reticular volume to body weight ratio is an adaptation to exploiting thick cell-walled, high cellulose diets (i.e., graminoids); and (3) low rumino-reticular volume to body weight ratio is an adaptation to exploiting thin but lignified cell-walled diets (i.e., browse).
    • The Effects of Burning on Mineral Contents of Flint Hill Range Forages

      Umoh, J. E.; Harbers, L. H.; Smith, E. F. (Society for Range Management, 1982-03-01)
      The mineral status of Flint Hills bluestem forage was assessed monthly between 1975 and 1976. Results indicated that magnesium, potassium, and manganese were adequate for optimum performance of range cattle during spring and summer, but that magnesium and potassium were low in late fall and winter. Concentrations of calcium, iron, and zinc, highest in spring, were higher throughout the year than established nutrient requirements. Burning significantly decreased phosphorus and iron and increased magnesium. The low levels of phosphorus and potassium during fall and winter do not affect animal performance.
    • Small Mammal Populations in an Unburned and Early Fire Successional Sagebrush Community

      McGee, J. M. (Society for Range Management, 1982-03-01)
      Species composition and total numbers of small mammals changed little in the unburned sagebrush while individual species capture rates varied considerably. Following spring burning, the number of small mammal species and abundance were slightly lower than control levels and were near unburned levels after 3 years. Species composition was greatly reduced on the fall burn in the first postburn year. Two years after burning four species were captured, although only two were caught in live-traps. Total small mammal density increased dramatically in the first two postburn years. The large increase in abundance on both burns was due primarily to Peromyscus maniculatus and Spermophilus armatus. Food use patterns on the fall burn were similar to those observed on the spring burn where small mammals utilized their preferred food types in relation to its abundance and availability.
    • Sample Preparation Techniques for Microhistological Analysis

      Holechek, J. L. (Society for Range Management, 1982-03-01)
      A study was conducted to determine the influence of sample preparation procedures on the ratio of identifiable to nonidentifiable fragments in diet samples analyzed by microhistological analysis. The number of identifiable fragments on slides was significantly higher when samples were soaked in either bleach or sodium hydroxide in conjunction with use of Hertwig's clearing solution compared to the control, which involved the use of only Hertwig's clearing solution. The percentages by weight of grasses, forbs, and shrubs in two prepared diet samples were more accurately estimated when either sodium hydroxide or bleach was applied in comparison with the control. However, some plant species or plant parts may be destroyed by bleach or sodium hydroxide. Therefore, diet materials should also be examined through standard procedures before the decision is made to apply one of these treatments.
    • Root Biomass on Native Range and Mine Spoils in Southeastern Montana

      Holechek, J. L. (Society for Range Management, 1982-03-01)
      Research was conducted on native range and revegetated strip mine spoils near Colstrip, Montana, in August of 1975 to determine the weight and distribution of root biomass at five locations. Study sites included native range in excellent, good, and poor condition; a naturally revegetated 40-year-old leveled, ungrazed strip mine spoils; and a 5-year seeded and fertilized mine spoils. Total root biomass was highest on the 5-year-old seeded and fertilized mine spoils. Good condition native range had a higher root biomass than excellent or poor condition native range. The root biomass of the 40-year-old mine spoil did not differ from excellent condition native range. Root biomass distribution in the four zones studied did not differ between sites. Over 55% of the root biomass was in the upper 15 cm of the soil profile at all five locations.
    • Responses of Crested Wheatgrass and Russian Wildrye to Water Stress and Defoliation

      Mohammad, N.; Dwyer, D. D.; Busby, F. E. (Society for Range Management, 1982-03-01)
      Crested wheatgrass (Agropyron desertorum, Fisch Schult) and Russian wildrye (Elymus junceus, Fisch) plants were subjected to three levels of water stress (13, 2.6, and 1.8% soil moisture), in interaction with 4 defoliation levels (0, 40, 60, and 80% defoliation). Plants were clipped biweekly using the height-weight ratio method to determine the assigned defoliation level and leaf water potential $(\Psi _{1})$ was measured by pressure bomb. Following the final clipping at ground level a 40-day recovery period was allowed while maintaining plants at field capacity (13% soil moisture). Leaf water potential measurements showed significant differences between species, among three water stress levels, and within four defoliation levels. Water stress and defoliation levels significantly affected foliage yield, root biomass, and plant recovery. Heavy defoliation (80%) resulted in a 100% death loss for both species at wilting point (1.8% soil moisture). Light defoliated (40% at field capacity) produced more total dry matter than undefoliated plants maintained at field capacity or wilting point. Maximum root biomass was found in undefoliated plants of crested wheatgrass grown at field capacity. Significant differences in root production were also found among water stress and defoliation treatments. No plant recovery occurred among plants maintained at wilting point and defoliated at 80%. However, plants defoliated at 40 and 60% under 13 and 2.6% soil moisture exhibited considerable regrowth. In general crested wheatgrass out-yielded Russian wildrye in every treatment and was more resistant to defoliation and water stress.
    • Response of Needle-and-Thread and Western Wheatgrass to Defoliation by Grasshoppers

      Burleson, W. H.; Hewitt, G. B. (Society for Range Management, 1982-03-01)
      Field and greenhouse studies were conducted to measure changes in plant growth resulting from grasshopper defoliation. All data indicated that as grasshopper grazing intensity on needle-and-thread grass increased, total root weight decreased. A greenhouse study with western wheatgrass showed that heavy grazing (80% removal of top growth) for a 16-day period reduced top growth 82%, root growth 85%, crown growth 81%, rhizome growth 100%, and depth of root penetration 49%. Field observations indicated that most grasshopper defoliation of needle-and-thread grass and western wheatgrass occurs after seasonal growth has been completed.
    • Rapid Extraction of Sesquiterpene Lactones from Sagebrush for Use as Taxonomic Markers

      Kelsey, Rick G. (Society for Range Management, 1982-03-01)
      The sesquiterpene lactones of sagebrush occur in glandular trichomes on the leaf surface and can be extracted in 1 to 2 minutes with chloroform. Analysis of this extract by thin-layer chromatography can be used as a taxonomic characteristic.
    • President's Address

      Merrill, John L. (Society for Range Management, 1982-03-01)
    • Potassium Content of Three Grass Species during Winter

      Hinnant, R. T.; Kothmann, M. M. (Society for Range Management, 1982-03-01)
      The potassium content of little bluestem (Schizachrium scoparium (Michx.) Nash), kleingrass (Panicum coloratum L.), and brownseed paspalum (Paspalum plicatulum Michx.) declined following plant senescence and frost. The potassium content of herbage of little bluestem and brownseed paspalum reached levels below the requirements of cattle by February during two winters. Kleingrass leaves retained green tissue the first winter yielding higher potassium levels. Little bluestem had reached senescence and had low levels of potassium by November. Herbage of the three species was also subjected to soaking treatments to simulate frost damage and quantify losses due to leaching. Potassium levels declined with soaking in freeze damaged herbage as time of exposure increased. Soaking treatments did not significantly affect the potassium content of fresh live herbage.
    • Nutrient Testing of Soil sto Determine Fertilizer Needs on Central Sierra Nevada Deer-Cattle Ranges

      Evans, R. A.; Neal, D. L. (Society for Range Management, 1982-03-01)
      Soil samples representing six major forest soil series and two meadow unclassified types were collected from 17 locations on critical deer migration routes in the central Sierra Nevada, California. Nutrient tests were conducted in the greenhouse using soft chess (Bromus mollis) as an indicator species to determine deficiencies of nitrogen, phosphorus, and sulfur. These tests were carried out to assess fertilizer needs and the probability of field response to increased nutrient levels in the soil for improvement of forage quality and quantity on deer migration routes. All soils were nitrogen deficient; the meadow soils were less so than the forest soils. In 94% of the soils samples, the addition of phosphorus (70%) or phosphorus and sulfur (24%) with nitrogen increased plant yields dramatically (as much as 26 times) compared with adding nitrogen alone. Addition of sulfur with nitrogen produced a yield response equal to that produced by phosphorus or phosphorus plus sulfur with nitrogen in three soils. Nitrogen was the nutrient most limiting for plant growth; phosphorus was next important and was essential for best response in most soils. Sulfur produced variable responses, usually increasing plant yields only after nitrogen and phosphorus deficiencies were corrected. Productivity of forage and browse species growing on these soils is determined by nutrient status; characteristics delineated at the series level, such as depth, texture, and structure; and moisture-temperature relations in specific years.
    • Level Benches for Forage Production in the Northern Plains

      Rauzi, F.; Landers, L. (Society for Range Management, 1982-03-01)
      Level benches 4- and 8-m-wide were constructed at the Wyoming Agriculture Research and Extension Center, Gillette, Wyoming 1970. Replicated benches and controls were seeded with Ladak alfalfa, Nordan crested wheatgrass, intermediate wheatgrass, and mixtures of Ladak alfalfa and crested and intermediate wheatgrass. Phosphorus (134 kg P2O5/ha) was applied to all benches and to the control. Ammonium nitrate was applied at 90 kg N/ha in May 1972 and 1977, and at 45 kg/ha in April 1974 to the benches and control, except those seeded to alfalfa alone. Snow trapped in the benches was not uniformly distributed because of the benches' northeast orientation. However, more soil water was available for plant use. The deep-rooted alfalfa was compatible with the shallow-rooted crested wheatgrass and seemed the best combination tested for forage production on level benches in northeast Wyoming. Construction of level benches is a practice that can ensure a dependable source of quality feed by trapping and holding snow for onsite use. Forage yields from the henches and the controls varied with years. During the 8 years (1970-1978) on the 4- and 8-m-wide benches, alfalfa yields averaged 3,420 and 3,813 kg/ha, respectively, and alfalfa and crested wheatgrass mixture averaged 3,560 and 3,855 kg/ha, respectively. Crested wheatgrass alone on 4- and 8-m-wide benches averaged 2,569 and 2,456 kg/ha, respectively, and on the 4- and 8-m-wide control averaged 2,382 and 2,786 kg/ha, respectively. Intermediate wheatgrass on the 4- and 8-m-wide benches averaged 2,329 and 3,425 kg/ha, respectively, and on the 4- and 8-m-wide controls averaged 2,565 and 3,262 kg/ha, respectively. Grass yields did not differ significantly when grasses were grown alone on the benches or on the control.
    • Infiltration and Sediment Production on a Deep Hardland Range Site in North Central Texas

      Brock, J. H.; Blackburn, W. H.; Haas, R. H. (Society for Range Management, 1982-03-01)
      Greatest infiltration rate and lowest sediment production occurred in the honey mesquite canopy zone. Infiltration on shortgrass interspace areas was about one-half of the canopy zone rate. Terminal infiltration rates within the canopy zone and shortgrass interspace areas were affected little by brush control treatments. Infiltration rate improvement due to treatment occurred primarily in the midgrass interspace areas. Water-stable aggregates and the interaction of soil aggregate stability with the amount of bare ground were the dominant factors controlling infiltration. Sediment production on the shortgrass interspace was double that of the canopy zone or midgrass interspace areas. Low rate of sediment production on the midgrass interspace areas occurred on areas aerially sprayed or root plowed 3 years earlier. Sediment production was controlled primarily by an interaction of soil organic matter and amount of above-ground biomass or grass cover.
    • Increasing the Rate of Cattle Dung Decomposition by Nitrogen Fertilization

      Lussenhop, J.; Wicklow, D. T.; Kumar, R.; Lloyd, J. E. (Society for Range Management, 1982-03-01)
      Cattle dung on a Colorado range was subjected to 6 years of irrigation and nitrogen fertilization. Disappearance of the dung was determined by sampling particles >0.8 cm2. No particles remained in irrigated plots. Seventy-two percent less dung weight remained in nitrogen fertilized than in control plots. Nitrogen fertilization increased dung nitrogen concentration by 13%. We argue that fertilization increased weight loss by stimulating microbial growth.
    • In Vitro Digestion—Sources of Within- and Between-Trial Variability

      Milchunas, D. G.; Baker, D. L. (Society for Range Management, 1982-03-01)
      Procedures for, and conditions during, inoculum collection and preparation, digestion, and residue recovery stages of the in vitro digestion technique were investigated to determine sources of within- and between-trial variability in digestion coefficients for forages of different chemical composition. Digestion coefficients differed significantly among inoculum preparation times of 1, 2, and 4 hours and for a decline in rumen fluid temperature to 29° in transport. These differences were not uniform across forage species and did not correlate with forage digestibility. Digestion coefficients differed significantly among inoculums prepared from fibrous deer rumen fluids that were strained only, strained and layered, and blended in a Waring blender and filtered through glass wool but did not differ between strained-layered and blended filtered inoculums of non-fibrous rumen fluid from a fistulated cow. Forage in vitro digestion in the absence of microbial activity (by solubility alone) indicated that forages having more soluble components were least affected by inoculums of different microbial activities, suggesting that between-trial differences be adjusted by a solubility, rather than a digestibility, factor. Inoculum nitrogen concentration did not correspond to between-trial differences in forage digestibility. Size of test tube, but not centrifugation versus filtration method of residue preparation, significantly affected digestion coefficients. However, because the standard large tube size cannot be centrifuged, the two methods of residue recovery would not be comparable unless the products of digestion were transferred from large tubes to centrifuge tubes. The end products of digestion must be stored under refrigeration if filtering proceeds for extended periods of time.
    • Grass Response Following Thinning of Broom Snakeweed

      McDaniel, K. C.; Pieper, R. D.; Donart, G. B. (Society for Range Management, 1982-03-01)
      Complete removal of broom snakeweed resulted in perennial grass production 833% of that on untreated rangeland after one growing season, and 712% and 300% the second and third year, on a pasture heavily grazed and in poor range condition. On a moderately grazed pasture in good range condition, grass standing crop increased 42% the first year, 81% the second, and 25% the third compared to untreated rangeland. Perennial grass production on the heavily grazed pasture was far below that on the moderately grazed pasture at the start of the study (40 vs 454 kg/ha). After 3 years, with complete broom snakeweed removal and no grazing, perennial grass production was comparable on the pastures once heavily and moderately grazed (1014 vs 939 kg/ha, respectively).