• N and P fertilization on rangeland production in Midwest Argentina

      Guevara, J. C.; Stasi, C. R.; Estevez, O. R.; Le Houérou, H. N. (Society for Range Management, 2000-07-01)
      Low soil nutrient status may be the major limiting factor to forage production in rangelands of the Mendoza plains 4 years out of 10. We studied vegetation responses to annual applications of N and P on such rangelands. Fertilizer application rates were 0 or 25 N and 0 or 11 P (kg ha-1) in a factorial arrangement. Dry matter production of grasses and palatable shrubs and crude protein (CP) content of grasses were determined annually from 1996 to 1998. Experimental plots received rains of 189, 278, and 346 mm during the 3 study years compared to mean growing season rainfall of 258 mm. Forage production was increased by N+P fertilization only in 1998 (1,390 vs 980 kg ha-1, P 0.05), producing 16.5 kg forage kg-1 N applied. Crude protein concentration was increased by N fertilization in 1997 (6.3 vs 5.3%, P < 0.05) and N+P application increased in 1998 (6.8 vs 5.7%, P < 0.05). Nitrogen and P application increased seasonal rain-use efficiency when the rainfall exceeded 300 mm. In 1998, the increase of grass production per kg N applied with and without P was 18.4 and 12.4 kg, respectively. The break-even point between rain and nutrients as the main primary production determinant on sandy soils in the central Mendoza plains is around 400 mm year-1 instead of 300 mm in other arid lands of the world. The value of meat increment derived from the N fertilization, with and without P application (US 0.07 ha-1 year-1 kg-1 N) was lower than the fertilizer cost (US 0.87 kg-1 N). A 5-fold increase in forage yields would be required to offset the cost of fertilizer. Fertilizer application did not increase forage production enough to be profitable for cattle production at present fertilizer and meat prices.
    • N, P, And K Fertilization of Tall Fescue (Festuca arundinacea Schreb.) Overseeded Range in Eastern Oklahoma

      Mitchell, R. L.; Ewing, A. L.; McMurphy, W. E. (Society for Range Management, 1985-09-01)
      A native hay meadow in northeastern Oklahoma was overseeded with tall fescue (Festuca arundinacea Schreb.) and fertilized for 6 years with N in August and February to encourage tall fescue growth in late fall and early spring, thus extending the green forage season. The effect of P and K fertilizer on forage yield and plant nutrient concentration was determined. Cool-season N fertilization (112 kg/ha) nearly doubled tall fescue yield and increased forage nitrogen concentration without altering warm-season grass production. Additions of P (15, 29 kg/ha) and K (28, 112 kg/ha) increased cool-season forage yield marginally and increased fertilizer N recovery but had no desirable effect on forage N, P, and K content. Tall grass decreaser species were dominant at the end of the study. Available soil P increased with P fertilization and available soil K increased with K fertilization.
    • N-alkane as an internal marker for predicting digestibility of forages

      Sandberg, R. E.; Adams, D. C.; Klopfenstein, T. J.; Grant, R. J. (Society for Range Management, 2000-03-01)
      Independent digestion trials with 5 forages were conducted to compare n-alkane with indigestible acid-detergent fiber (IADF) as internal markers to predict in vivo dry matter digestibility (digestibility). Forages were mixed grasses from subirrigated meadow (meadow), meadow regrowth (regrowth), native range (range), mature mixed grass hay from meadow, and alfalfa (Medicago sativa L.) hay. Meadow, regrowth, and range diets were immature grasses harvested 0.5 hours before feeding. Feces from the meadow hay and alfalfa hay trials were divided to compare freeze drying and oven drying (60 degrees C). All diets were subjected to in vitro fermentation for 0, 48, or 96 hours. N-alkane was separated from samples by 4.5-hour saponification with alcoholic KOH followed by extraction with n-hexane. Indigestible ADF was measured by 96-hour in vitro fermentation followed by ADF extraction. Digestibility estimated by markers was compared with in vivo digestibilities. N-alkane based digestibilities were lower (P < 0.01) than in vivo digestibility for all diets. N-alkanes provided higher estimates of digestibilities than IADF for meadow (P < 0.01), regrowth (P = 0.06), and alfalfa hay (P = 0.06), and lower digestibility for meadow hay (P = 0.02). Digestibilities calculated using n-alkanes for range tended to be higher (P = 0.14) than IADF values. Freeze drying increased (P < 0.01) the amount of n-alkane extracted from alfalfa hay, but did not affect (P = 0.1) the amount extracted from meadow hay. N-alkane disappeared (P < 0.001) from residue collected after 48 hours of in vitro fermentation, but no additional disappearance (P = 0.78) was evident at 96 hours. Neither marker was completely recoverable, although recovery of n-alkane was higher than indigestible ADF for 4 of the 5 forages tested.
    • Nail-Board Method of Root Sampling

      Schuster, J. L.; Wasser, C. (Society for Range Management, 1964-03-01)
    • Nara Desert, Pakistan: Part I: Soils, Climate, and Vegetation

      Qureshi, Rahmatullah; Bhatti, G. Raza (Society for Range Management, 2005-10-01)
    • Nara Desert, Pakistan: Part II: Human Life

      Qureshi, Rahmatullah; Bhatti, G. Raza (Society for Range Management, 2005-10-01)
    • Nara Desert, Pakistan: Part IV: Destruction of Natural Habitats and Its Impact on Plant Diversity

      Qureshi, Rahmatullah; Bhatti, G. Raza (Society for Range Management, 2007-02-01)
    • Nara Desert, Sindh, Pakistan: Part III: Range Types and Their Plant Resources

      Qureshi, Rahmatullah; Bhatti, G. Raza (Society for Range Management, 2007-02-01)
    • National Animal Identification and the Elephant in the Room

      Skaggs, Rhonda; Crawford, Terry (Society for Range Management, 2007-04-01)
    • National Assessment and Critiques of State-and-Transition Models: The Baby with the Bathwater

      Bestelmeyer, Brandon T. (Society for Range Management, 2015-12-01)
      On the Ground • Ecological site descriptions and state-and-transition models are national-level tools for organizing and delivering information about landscape dynamics and management. • Recent papers criticized state-and-transition models because they overemphasize grazing, are inconsistentlypresented, and do not address climate change. • I argue that the analysis of Twidwell et al. does not support an overemphasis on grazing, that inconsistent presentation is a necessary consequence of early model development efforts and immature science concepts, and that climate change effects should not be addressed in site-level models without evidence. • Improving these important tools requires fair critique, but also the strong commitment of scientists and funders.
    • National Meetings Are Also for Students

      Sedgley, Ellis F. (Society for Range Management, 1953-09-01)
    • National Public Attitudes toward Federal Rangeland Management

      Brunson, Mark W.; Steel, Brent S. (Society for Range Management, 1994-04-01)
    • National Range Judging Contest

      Williams, Angela S. (Society for Range Management, 1997-12-01)
    • National Rangeland Hydrology Study

      Flanagan, Mitch (Society for Range Management, 1992-08-01)
    • National Security and Rangelands

      Holechek, Jerry L. (Society for Range Management, 2007-10-01)
      Depletion of fossil fuels and global warming could drastically reduce world food production. Conserving and improving rangelands is important, because they likely will play an increased role in meeting world food needs.
    • Native American Management and the Legacy of Working Landscapes in California

      Diekmann, Lucy; Panich, Lee; Striplen, Chuck (Society for Range Management, 2007-06-01)
      Western landscapes were working long before Europeans arrived.
    • Native forage quality, quantity, and profitability as affected by fertilization in northern Mexico

      Rubio, H. O.; Wood, M. K.; Gomez, A.; Reyes, G. (Society for Range Management, 1996-07-01)
      Fourteen treatments of nitrogen (N) and phosphorus (P) fertilizers were applied in an overgrazed eight rangeland in northern Mexico, during 1990 and 1991. Eight treatments were applied using ammonium nitrate as a source of N (60-0-0, 60-30-0, 60-60-0, 80-40-0, 120-30-0, 120-60-0, 120-90-0 and 180-60-0 kg ha-1), 2 treatments with ammonium sulfate (60-30-0 and 120-60-0 kg ha-1), 2 with urea (60-30-0 and 120-60-0 kg ha-1), only P (0-30-0 kg ha-1), and the control (0-0-0 kg ha-1). Triple superphosphate was applied as a source for P. The 80-40-0 treatment was included because it was the commonly recommended rate for the area. Fertilizers were applied at the beginning of the rainfall season (July) and forage was harvested in late October (1990) and mid-November (1991). Dry matter production, crude protein (CP) content, and in situ digestibility were determined. An economic analysis was used to obtain the best economic treatment for forage production. In 1990 with a precipitation of 377 mm, dry matter production was significantly affected for both source and rate of N. The maximum amount of dry matter was obtained with a rate of 120-90-0 kg ha-1 using ammonium nitrate. However, the best treatment in terms of economic return was 120-30-0 kg ha-1 as ammonium nitrate. Urea did not produce as well as other N source treatments. Crude protein was highest in treatments with the higher N, but no significant trend was evident. In situ digestibility was not affected by rate or source of N fertilizer. During 1991, precipitation was higher than in 1990. Significant differences were determined among N rates but not in N source. In fact, urea produced greater in dry matter production than other N sources at the same rate. The maximum amount of dry matter was obtained with the 180-60-0 treatment using ammonium nitrate with 4,190 kg ha-1, but the best economic treatments were the 120-30-0 and 60-0-0 with a marginal return rate of 377% and 355%, respectively. Results of CP and in situ digestibility were similar to those of 1990.
    • Native Grass Leaps to the Sun

      Farmer, Frank (Society for Range Management, 1979-06-01)
    • Native or seeded rangeland for cows with high or low milk production

      Adams, D. C.; Staigmiller, R. B.; Knapp, B. W.; Lamb, J. B. (Society for Range Management, 1993-11-01)
      Multiparous cows (n = 91, 1986; n = 92, 1987) were selected from 2 populations to obtain cattle with high and low milk production. After March-April calving, high and low producing cows grazed either native range (treatment 1) or seeded range (treatment 2) until weaning in September. Seeded range included paddocks of crested wheatgrass (Agropyron desertorum, Fisch. ex [Link]Schult), contour furrowed native range interseeded with "Ladak" alfalfa (Medicago Sativa L.), and Russian wildrye grass Psathrostachys juncea[Fisch.]Nevski.). In treatment 2, crested wheatgrass was grazed mid-April to 17 June, followed by contour furrowed rangeland 18 June to 5 August, and ended with Russian wildrye 6 August to weaning (mid-September). Data were analyzed as a split plot with treatment and year in the main plot and cow type in the subplot. Number of cows exhibiting estrus before the beginning of the breeding season and fall pregnancy rate were not influenced (P > 0.05) by range treatment. Twelve-hour milk production during May, June, August, and September ranged from 11.3 to 6.8 kg and 7.6 to 3.9 kg for high and low producing cows, respectively. Cows with high milk production lost body condition during and after the breeding season, whereas cows with low milk production maintained body condition during the same period. Live weight gain of calves was greater (P < 0.01) for cows with high production than cows with low production but was not affected (P > 0.05) by range treatment. We concluded that native and seeded ranges were of similar nutritive value for cows with high and low milk production and that cows with high milk production may have greater nutrient requirements during late summer-early fall than what was provided by native or seeded ranges. Protein may be the primary limiting nutrient in forages during the late summer for lactating cows grazing Northern Great Plains range.
    • Native Plant Growth and Seedling Establishment in Soils Influenced by Bromus tectorum

      Rowe, Helen I.; Brown, Cynthia S. (Society for Range Management, 2008-11-01)
      The invasion of 40 million hectares of the American West by cheatgrass (Bromus tectorum L.) has caused widespread modifications in the vegetation of semi-arid ecosystems and increased the frequency of fires. In addition to well-understood mechanisms by which cheatgrass gains competitive advantage, it has been implicated in reducing arbuscular mycorrhizal fungi (AMF) abundance and taxa diversity. We evaluated this possibility at a high elevation site in a two-pronged approach. To test whether cheatgrass changed native AMF communities in ways that affected subsequent native plant growth, we grew cheatgrass and native plants in native soils and then planted native plants into these soils in a greenhouse experiment. We found that cheatgrass-influenced soils did not inhibit native plant growth or AMF sporulation or colonization. To test whether soils in cheatgrass-dominated areas inhibited establishment and growth of native plants, cheatgrass was removed and six seeding combinations were applied. We found that 14.02 +/- 1.7 seedlings m-2 established and perennial native plant cover increased fourfold over the three years of this study. Glyphosate reduced cheatgrass cover to less than 5% in the year it was applied but did not facilitate native plant establishment or growth compared with no glyphosate. We conclude that cheatgrass influence on the soil community does not appear to contribute to its invasion success in these high elevation soils. It appears that once cheatgrass is controlled on sites with sufficient native plant abundance, there may be few lingering effects to inhibit the natural reestablishment of native plant communities.