Journal of Range Management, Volume 39, Number 1 (January 1986): Recent submissions
Now showing items 21-26 of 26
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Diet of Guanaco and Red Deer in Neuquen Province, ArgentinaSpring and summer diets of guanaco (Lama guanicoe) and red deer (Cervus elaphus) in northern Patagonia were determined by the microhistological analysis of their droppings. Forbs were the main components of the guanaco diet both in spring and summer. Spring diet of deer was comprised mainly of grasses, whereas the summer was comprised equally of trees, shrubs, forbs and grasses. These results indicate differential use of the area by both species.
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Construction of an Inexpensive Liquid Resin Esophageal Cannula for GoatsA simple method for construction of esophageal cannulas for goats employing liquid polyestyrenic resin is described. They were made with easily available and low cost materials.
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Combination of Weight Estimates with Clipped Sample DataWeight estimation is a common procedure to determine range forage production. In this method clipped samples are used to train an observer, to make periodic checks on observer performances, and to compute estimated/clipped conversion factors. The clipped sample data are then discarded. This is in contrast to a double sampling procedure where both clipped values and estimated values are used in computation of sample variance. However, if both estimated values and clipped plots are taken at random, they can be combined to compute sample means and variances by using techniques appropriate to combining data of different variances. The efficiency of the combined sample appears to be greater than that of formal double sampling and also has the advantage that plots clipped for training and checking can also be used as part of the sample.
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Annual Medics and Related Species as Reseeding Legumes for Northern Utah PasturesLegumes are beneficial in providing high quality forage and enhancing fertility levels in the soil by biological nitrogen fixation. Nonperennial Medicago species have a world-wide distribution and have been used successfully for grazing in Mediterranean-type environments. The feasibility of using nonperennial Medicago species as reseeding pasture legumes in the northern Utah area was evaluated at 2 locations in replicated plantings of 584 accessions representing 34 Medicago species. These nurseries were planted in the spring of 1981 and data were collected through the 1983 growing season. Most of the species were easily established at both test sites. Many grew more rapidly during the seeding year than did the perennial check, M. falcata L. However, no annual or biennial species was as well nodulated or reduced acetylene on a per plant basis as well as M. falcata. None of the populations matured, reproduced, and initiated soil seed bank at the droughtier of the 2 locations. M. laciniata (L.) Mill., M. lupulina L., M. murex Willd., and M. muricoleptis Tin. excelled in the numbers of seedlings per meter of area established by natural reseeding in the fall of the first year of test. However, only M. lupulina (black medic) produced abundant seedlings during the second year following seeding. Results indicated that M. lupulina could develop a soil seed bank more rapidly than the other species. Black medic also had superior ground cover characteristics during the second and third years after sowing. Adapted populations of M. lupulina appear to have long-term value for forage production in Utah rangeland pastures with suitable soils and adequate precipitation.
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Anagyrine in Western American LupinesThe teratogenic condition known as 'crooked calf disease' occurs when pregnant cows eat certain lupines with anagyrine concentrations at or above 1.44 g kg-1 dry matter between the 40th and 70th day of pregnancy. Five of eight species collected in Oregon and Washington had accessions with anagyrine at or above the hazardous concentrations as determined by gas/liquid chromatography. A total of 14 species of lupine are now shown to contain accessions with potentially hazardous concentrations of anagyrine. Any range/livestock management system that will expose susceptible cattle to anagyrine-bearing lupines could result in serious calf crop losses.
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Alfalfa Survival and Vigor in Rangeland Grazed by SheepFew detailed comparisons have been made among alfalfa (Medicago spp.) cultivars and strains grazed in semiarid, rangeland environments. The objective of this study was to determine survival and vigor of alfalfa cultivars and experimental strains that were grown in association with rangeland grasses and grazed by sheep for 3 seasons. Three-month old seedlings of 5 cultivars and 6 experimental strains of winterhardy alfalfa were transplanted in June 1979 into grass sod on 0.9-m centers at a hillside site with a west-facing 16% slope and Amor loam (Typic Haploboroll) soil. Dominant vegetation was western wheatgrass (Pascopyrum smithii (Rydb.) Löve. Syn: Agropyron smithii (Rydb.)], blue grama [Bouteloua gracilis (H.B.K.) Lag.], and smooth bromegrass (Bromus inermis Leyss.). For 3 seasons after the establishment year, each replicate was grazed in sequence for 2 weeks at a stocking rate of 48 yearling ewes/ha during summer and then mowed to a height of 10 cm in September. Only 5 of the 11 entries had greater than 50% survival after the third season. Three germplasm pools derived from local alfalfa plantings that had persisted more than 50 years in association with rangeland grasses were highest in survival, ranging from 72-74%. Drylander and Roamer, 2 cultivars developed primarily for grazing in semiarid regions of western Canada, had 65 and 62% survival, respectively. Phenotypic variability found among surviving plants in this study will permit further genetic improvements in alfalfa for rangeland.
