• Understory responses to mechanical treatment of pinyon-juniper in northwestern Colorado

      Stephens, G.J.; Johnston, D.B.; Jonas, J.L.; Paschke, M.W. (Society for Range Management, 2016)
      Pinyon-juniper (Pinus spp.-Juniperus spp.) encroachment and decliningmule deer (Odocoileus hemionus) populations in western Colorado have necessitated management for increased forage. Pinyon-juniper removal is one such technique; however, it is unclear which method of tree removal most effectively promotes forage species. We conducted an experiment to quantify understory responses to mechanical pinyon-juniper removal and seed additions in a blocked design using three different methods: anchor-chaining, rollerchopping, and mastication. Blocks contained each mechanical and seeding treatment along with an untreated control. Seven blocks across two sites, North Magnolia (NM, 4 blocks) and South Magnolia (SM, 3 blocks), were treated during the fall of 2011. Half of each plot was seeded before or during mechanical treatment with a mix of grasses, shrubs, and forbs. After two growing seasons, biomass of perennial grasses was 90-160 kg · ha-1 in mechanically treated plots compared with 10 kg · ha-1 in untreated controls. There were no differences, however, between mechanical treatments for any perennial plant species. Response of annual plant species depended on mechanical treatment type and site. Rollerchopping had higher exotic annual grass cover than mastication or control at NM and higher exotic annual forb cover than chaining or control at SM. Rollerchopping was the only treatment to have higher native annual forb cover than control in the absence of seeding. Seeding increased native annual forb biomass in mastication compared with control. Seeding also increased shrub density at SM, which had fewer shrubs pretreatment relative to NM. Results suggest any type of mechanical removal of pinyon-juniper can increase understory plant biomass and cover. Seeding in conjunction with mechanical treatments, particularly mastication, can initially increase annual forb biomass and shrub density. Finally, different understory responses between sites suggests that pretreatment conditions are important for determining outcomes of pinyon-juniper removal treatments. © 2016 The Authors. Published by Elsevier Inc. on behalf of The Society for Range Management. This is an open access article under the CC BY-NC-ND license.
    • Understory species response to Utah juniper litter

      Horman, C. S.; Anderson, V. J. (Society for Range Management, 2003-01-01)
      A greenhouse study was conducted to determine the effects of litter leachate and litter depth of Utah juniper [Juniperus osteosperma (Torr.) Little] on seedling emergence and emergence rate of 8 common herbaceous understory species. Species tested were: ‘Secar’ bluebunch wheatgrass [Pseudoroegnaria spicata (Pursh) A. Love], bottlebrush squirreltail [Elymus elymoides (Raf.) Swezey], cheatgrass (Bromus tectorum L.), ‘Paiute’ orchardgrass (Dactylis glomerata L.), ‘Appar’ Lewis flax (Linum lewisii Pursh), ‘Delar’ small burnet (Sanguisorba minor Scop.), antelope bitterbrush [Purhsia tridentata (Pursh) DC.], and mountain big sagebrush [Artemisia tridentata spp. vaseyana (Rydb.) J. Boivin]. Three water treatments (distilled water, 1%, and 10% litter leachates) and 3 litter depths (0, 3, and 5 cm) were tested. Leachates decreased seedling emergence of orchardgrass and small burnet. Emergence rate was unaffected by leachate treatments. Seedling emergence of all species tested decreased significantly with increasing litter depth. Emergence rate was initially slower in pots with litter, but after 2 weeks no differences were found.
    • Understory Vegetation and Ponderosa Pine Abundance in Eastern Oregon

      Carr, Craig A.; Krueger, William C. (Society for Range Management, 2011-09-01)
      Management prescriptions for contemporary ponderosa pine (Pinus ponderosa Dougl.) forests often incorporate the restoration to a structure that more closely resembles pre-European contact forests. Successful restoration programs should incorporate the herbaceous understory component; however, published research specifically addressing changes in understory species composition is minimal. Ponderosa pine influence on the undercanopy environment may be an important factor in understory vegetation distribution. In this study, we addressed the relationships among ponderosa pine abundance, undercanopy environment, and understory species composition and made inferences with respect to restoration potential. Data representing vegetation, soil, and environmental attributes were measured in 28 plots in an eastern Oregon ponderosa pine forest. Relationships among the parameters measured were evaluated using cluster analysis, indicator species analysis, and ordination. Ponderosa pine occupancy was inversely related to understory perennial bunchgrass abundance and species diversity and appeared to regulate the undercanopy habitat through alterations in light intensity, nitrogen availability, and soil temperature. Light availability was the most important ponderosa pine-influenced undercanopy environmental parameter associated with understory vegetation distribution. These data suggested that degradation in the undercanopy environment associated with higher levels of ponderosa pine abundance may be temporary and that restoration practices that reduce pine occupancy should promote undercanopy conditions favorable to perennial bunchgrass growth. However, understory vegetation recovery in stands with excessive pine ingrowth may be constrained by desired understory species loss or invasion by more competitive understory vegetation.
    • Understory-overstory relationships in ponderosa pine forests, Black Hills, South Dakota

      Uresk, Daniel W.; Severson, Kieth E. (Society for Range Management, 1989-05-01)
      Understory-overstory relationships were examined over 7 different growing stock levels (GSLs) of 2 size classes (saplings, 8-10 cm d.b.h. and poles, 15-18 cm d.b.h.) of ponderosa pine (Pinus ponderosa) in the Black Hills, South Dakota. Generally, production of graminoids, forbs, and shrubs was similar between sapling and pole stands. Trends among GSLs were also similar between these tree size classes. Graminoids and forbs were most abundant in clearcuts and the 5 m2/ha basal area. Intermediate amounts were produced at GSLs of 14-23 m2/ha and lowest in unthinned stands which had basal areas ranging from 27-33 m2/ha and 37-40 m2/ha in sapling and pole stands, respectively. Total understory production followed the same trends. Shrubs, however, appeared to produce most at intermediate stocking levels but were variable. Graminoid and forb production were best estimated by the model logY=a+bX. Relationships for total production were better described by Y=a+bX. However, variability of shrub production precluded selection of a single model; the best model varied between tree size classes. Standard errors of the estimate indicate that reasonably good predictive models can be developed for pole and sapling stands considered separately or combined. When years were combined, however, SEs increased markedly, indicating less reliable models.
    • Ungulate Diets in the Lower Grand Canyon

      Hansen, R. M.; Martin, P. S. (Society for Range Management, 1973-09-01)
      Plant fragments were identified and quantified by a microscopic examination of the dung of the burro, cattle, and bighorn in the western end of the Grand Canyon, Arizona. Genera of plants common to the diets of all three ungulates were: Sphaeralcea, Bromus, Tridens, Muhlenbergia, Acacia, Ephedra, Opuntia and Tidestromia. Wherever free ranging large herbivores occur, as in the Lake Mead National Recreation Area, it is possible to study their diets by analysis of their dung. The diet of modern large herbivores can be compared with the unique Pleistocene record of ground sloth and extinct mountain goat dung preserved for over 11,000 years in adjacent caves.
    • Ungulate foraging areas on seasonal rangeland in northeastern Oregon

      Sheehy, D. P.; Vavra, M. (Society for Range Management, 1996-01-01)
      In much of the west, seasonal rangeland provides important foraging opportunities for wild and domestic ungulates during times when forage is often limited. We studied the use of foraging areas by Rocky Mountain elk (Cervus elaphus nelsonii Bailey), mule deer (Odocoileus hemionus hemionus Rafinesque), and cattle grazing the same seasonal rangeland in northeastern Oregon. We determined the potential for ungulate use to overlap and the influence of vegetation and terrain features on that use. Vegetation and terrain features of plant communities in the Festuca-Agropyron and Agropyron-Poa Associations were inventoried on a 1,844 ha study area of privately owned seasonal rangeland to define characteristics of ungulate foraging areas. Slope, aspect, elevation and, edge between bunchgrass and forested vegetation types, were evaluated from topographic quadrats. Observations of ungulate distribution on the study area were also obtained. A Geographical Information System using map overlays intersected spatially defined plant communities and terrain features with location of ungulates. Indices of ungulate preference for plant communities and terrain features were established. Discriminant analysis was used to determine which features were most likely to influence ungulate selection of foraging areas. Terrain features having greatest influence on ungulate selection of foraging areas were, distance to the ecotonal edge between steppe and forest communities, and elevation. Cattle preferred foraging areas comprised of Idaho fescue-annual grass plant communities located at medium distance from the forest edge and on moderate elevation. Elk preferred foraging areas comprised of bluebunch wheatgrass-annual grass and Idaho fescue-bluebunch wheatgrass near the forest edge at higher elevations. Mule deer preferred buckwheat-bluegrass scabland plant communities at medium distance from the forest edge at higher elevation. Probability of ungulates using similar foraging areas was highest for elk and cattle and least for elk and mule deer.
    • Ungulate herbivory of willows on Yellowstone's northern winter range

      Singer, F. J.; Mark, L. C.; Cates, R. C. (Society for Range Management, 1994-11-01)
      Effects of unmanaged populations of large mammalian herbivores, especially elk (Cervus elaphus on vegetation is a concern in Yellowstone National Park, since wolves (Canis Lupus) are extirpated, ungulate migrations are altered by human activities and the disruption of natural process is possible. Stands of low, hedged (height-suppressed) willows (Salix spp.) are observed throughout the greater Yellowstone National Park area where high densities of wintering elk or moose (Alces alces) exist. The height of 47% of the willow stands surveyed on Yellowstone's northern winter range has been suppressed. Mean leader use of willows of all heights was (P < 0.05 in the winter of 1987-88, increased to 60% in winter 1988-89, following the drought and fires of 1988, then declined to 44% in 1989-90 and winter 1990-96. Height-suppressed willows (43 +/- 2 cm, mean +/- SE) were about one-half as tall as tall willows (83 +/- 4 cm). Percent twig use of suppressed willows in summer (25%) and winter (59%) was significantly more than for intermediate or tall stands (P < 0.05). Suppressed willows produced about one-fourth the aboveground annual biomass compared to taller willows; even after 27 or 31 years of protection, previously-suppressed willows produced only one-third the aboveground biomass of taller willows, suggesting suppressed willows grow on sites with lower growth potential. Growth conditions for willows on the northern winter range may have declined due to a warmer and drier climate this century, locally reduced water tables—because of the decline on beaver (Castor canadenis), or fire suppression may be responsible for the observed changes. Tall and intermediate-height willows contained higher concentrations of nitrogen and they exhibited more water stress than height-suppressed willows of the same species. More xeric growth conditions this century than last century, especially during the decades of the 1920's, 1930's, and 1980's, may explain the low growth rates and lower chemical defenses against ungulate herbivory for height-suppressed willows. We propose a more xeric climate and locally-reduced water tables likely contributed to the willow declines on the northern winter range, but that the proximate factor in the declines was herbivory by native ungulates.
    • Ungulate herbivory on buckbrush in an Arizona ponderosa pine forest

      Huffman, D. W.; Moore, M. M. (Society for Range Management, 2003-07-01)
      Monitoring processes that affect plant population dynamics and determine community structure is central in forest restoration ecology. To study effects of mule deer (Odocoileus hemionus) and elk (Cervus elaphus) on buckbrush (Ceanothus fendleri Gray), we built exclosures around 90 plant-centered plots in 3 ponderosa pine (Pinus ponderosa Laws.) forest restoration management units and compared vegetative and flowering characteristics with unprotected plots for 2 years. On unprotected plots, 69% of the current-year branches were browsed during the first year and 44% were browsed the second year. There was no difference in number of aerial stems or current-year branches in the first year, yet stems on protected plots were longer (24.1 cm; P < 0.01) and retained more than 4 times the current-year biomass (1.4 g stem-1; P < 0.01) than those on unprotected plots (12.9 cm and 0.3 g stem-1, respectively). Stem number, length and diameter, number of current-year branches, and current-year biomass on protected plots were all greater (P < 0.01) than on unprotected plots in the second year. Stems on protected plots had significantly higher (P < 0.01) length-diameter ratios and had fewer current-year branches per unit length (P < 0.05) than unprotected stems. Flowering stems were found on significantly (P < 0.05) more protected plots (55%) than unprotected plots (8%) in the second year. Effects of ungulate herbivores on buckbrush size, stem recruitment, morphology, and flowering represent important constraints to early understory development and restoration in this Southwest ponderosa pine forest.
    • Ungulate herbivory on Utah aspen: Assessment of long-term exclosures

      Kay, C. E.; Bartos, D. L. (Society for Range Management, 2000-03-01)
      The role of livestock grazing and big-game browsing in the decline of aspen (Populus tremuloides Michx.) in the Intermountain West has long been questioned. All known aspen exclosures (n=8) on the Dixie and Fishlake National Forests in south-central Utah were measured during late summer of 1995 and 1996 to determine aspen stem dynamics, successional status, and understory species composition. Five of the exclosures were of a 3-part design with a total-exclusion portion, a livestock-exclusion portion, and a combined-use portion which permitted the effects of deer (Odocoileus hemionus) and elk (Cervus elaphus) herbivory to be measured separately from those of livestock. Aspen within all total-exclusion plots successfully regenerated and developed multi-aged stems without the influence of fire or other disturbance. Aspen subjected to browsing by wildlife, primarily mule deer, either failed to regenerate successfully or regenerated at stem densities significantly lower (2,498 stems ha(-1)) than that on total-exclusion plots (4,474 stems ha(-1)). On combined wildlife-livestock-use plots, most aspen failed to regenerate successfully, or did so at low stem densities (1,012 stems/ha(-1)). Aspen successfully regenerated on ungulate-use plots only when deer numbers were low. Similarly, ungulate herbivory had significant effects on understory species composition. In general, utilization by deer tended to reduce shrubs and tall palatable forbs while favoring the growth of native grasses. The addition of livestock grazing, however, tended to reduce native grasses while promoting introduced species and bare soil. Thus, communities dominated by old-age or single-age trees appear to be a product of ungulate browsing, not a biological attribute of aspen as has been commonly assumed. There was no evidence that climatic variation affected aspen regeneration. Observed differences are attributed to varied histories of ungulate herbivory.
    • Unique Range School Works

      Anseth, Brad (Society for Range Management, 1980-02-01)
    • University of Texas Range Management Plan: A Premium on Livestock Management

      Allen, Dale D. (Society for Range Management, 1981-10-01)
    • Unwanted No More: Land Use, Ecosystem Services, and Opportunities for Resilience in Human-Influenced Shrublands

      Brunson, Mark (Society for Range Management, 2014-04-01)
      On the Ground • Shrub-dominated rangelands are highly susceptible to land degradation, partly because low land values can encourage neglect, leading to poor stewardship and/or conversion to more lucrative but ecologically less desirably uses. • Recent efforts to assess the value of “ecosystem services” show that commodity values don’t capture all the benefits of shrublands to society. • Efforts to prevent shrubland degradation and land type conversion can be enhanced if the value of noncommodity ecosystem services can be recognized. • Conceptual modeling of socio-ecological systems can point decision makers and stakeholders toward strategies to enhance shrubland resilience and protect ecosystem services.
    • Up in the Air: How might global warming and the greenhouse effect impact rangelands?

      El-Shatnawi, Moh’d K. J.; Ksiksi, Taoufik (Society for Range Management, 2001-08-01)
    • Update of the 2014 Drought on California Rangelands

      Larsen, Royce E.; Horney, Marc R.; Macon, Daniel (Society for Range Management, 2014-10-01)
      On the Ground • Droughts are common on California rangelands. • The current drought in California is listed as severe or exceptional for most of the state. • The drought has affected rangeland, and the livestock industry, more than other commodities. • The actual costs associated with this drought are just beginning to be realized.
    • Upland Bare Ground and Riparian Vegetative Cover Under Strategic Grazing Management, Continuous Stocking, and Multiyear Rest in New Mexico Mid-grass Prairie

      Danvir, R.; Simonds, G.; Sant, E.; Thacker, E.; Larsen, R.; Svejcar, T.; Ramsey, D.; Provenza, F.; Boyd, C. (Society for Range Management, 2018-02)
      We compared land cover attributes on rangeland pastures with strategically managed ranches (SGM), continuously stocked (CS), and rested pastures. SGM pastures had less upland bare ground and more riparian vegetative cover than adjoining CS pastures, and SGM pastures had bare ground cover comparable to pastures rested from grazing for three or more years. Differences in riparian cover between management types were greatest in years of near-average precipitation and lower in years of high precipitation or drought. Remote sensing technology provided a means of quantifying range condition and comparing management effectiveness on large landscapes in a constantly changing environment. © 2017 The Author(s)
    • Upland erosion under a simulated most damaging storm

      Linse, S. J.; Mergen, D. E.; Smith, J. L.; Trlica, M. J. (Society for Range Management, 2001-07-01)
      A 2 year study was conducted to determine the effects of surface cover and roughness on sediment yield from plots subjected to a simulated most damaging storm. This storm, based on long term sediment records from 3 Wyoming streams, produced approximately 18 mm of precipitation in 15 min with an intensity of 97 mm hour(-1). The rainfall simulator covered 2 plots; each 0.6 by 2 m. Plots were on 9% slopes with highly erosive soils (silt and fine sand texture) on native rangeland in 3 areas of Wyoming. Cover and surface roughness were measured with a point frame. Sediment production typically peaked approximately 120 sec after runoff started and reached steady state within 6 min. Plots with no cover (tilled) seldom produced runoff due to high infiltration and the short duration rainfall. Sediment yield was moderately correlated with total cover for total cover less than 30%, and sediment yield decreased to 0.1 tonnes ha(-1) (assumed allowable soil loss) or less for greater than 30% cover. There was a weak correlation between surface roughness and sediment yield, and surface roughness was slightly correlated with total cover. These results suggested that maintaining at least 30% total cover could control sediment yields from short duration-intense storms. Experimental results also indicated considerably higher sediment yields than those predicted by the Revised Universal Soil Loss Equation or a modified version of that equation.
    • Upland Water and Deferred Rotation Effects on Cattle Use in Riparian and Upland Areas

      Carter, J.; Catlin, J. C.; Hurwitz, N.; Jones, A. L.; Ratner, J. (Society for Range Management, 2017-06)
      Our experience shows that land management agencies rely on upland water and deferred rotation grazing systems to reduce riparian use and improve conditions, rather than addressing stocking rate and requiring herding of cattle. Range scientists have published studies showing that cattle prefer to linger in riparian areas and that stocking rate is more important than grazing system. We collected 4 years of data on upland and riparian residual vegetation, riparian stubble height, and bank alteration prior to implementation of the upland water developments and deferred rotation scheme and compared that with 4 years of data collected after implementation. As a result of this change in management, post-grazing riparian stubble heights decreased; bank alteration was unchanged; upland residual grasses were reduced; there was no change in residual herbaceous vegetation in the riparian zone; and utilization remained excessive in both upland and riparian areas. Range science shows that to reverse this outcome and improve conditions, changes must be made. These include o setting stocking rates based on currently available preferred forage species and today's consumption rates of livestock,o enforcing utilization rates of less than 30% in upland and riparian areas,o enforcing riparian stubble heights of > 15.2 cm across the aquatic influence zone and floodplain,o enforcing bank alteration levels of < 20%,o using riders to limit riparian use and distribute livestock, ando providing rest, not deferment, so that sensitive native grasses recover vigor and productivity prior to being grazed again. © 2017 The Authors
    • Upland Water and Deferred Rotation Effects on Cattle Use in Riparian and Upland Areas – A Reply to Carter et al. 2017

      Guttery, M.R.; Caudill, D. (Society for Range Management, 2019-04)
      A recent publication by Carter et al. (2017) presents research on the effects of deferred rotation grazing and water provisioning on a suite of environmental variables. We detail issues that call into question the validity of the results and conclusions reported by the authors. Data were not collected in a scientifically rigorous way. Sufficient detail is not presented for the study to be replicated. The authors do not adhere to standard statistical definitions or assumptions. The study suffers from unaccounted for pseudoreplication. The authors draw conclusions beyond the reasonable scope of inference.
    • Uptake of Available Selenium by Certain Range Plants

      Hamilton, J. W.; Beath, O. A. (Society for Range Management, 1963-09-01)
    • Urea as a Nitrogen Fertilizer for Great Plains Grasslands

      Power, J. F. (Society for Range Management, 1974-03-01)
      Economics and pollution standards indicate that urea may soon be the prime nitrogen fertilizer source in the Great Plains. Available literature was reviewed on the use of urea as a fertilizer for grasslands, particularly in semiarid regions. Results from only a few such experiments were found. However, these results agree with those from more humid or subtropical regions in that urea was as effective as ammonium nitrate at low, but not at high, rates of application. Maximum production attainable with urea is probably less than that attainable with ammonium nitrate.