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Item Comparison of Enrichment and Plating Media for Recovery of Virulent Strains of Yersinia enterocolitica from Inoculated Beef Stew(Elsevier BV, 1983-11) Schiemann, D.A.Five plating agar media were evaluated for their ability to recover pure cultures of virulent strains of Yersinia enterocolitica serotypes O:3, O:8 and O:5,27. Cellobiose-arginine-lysine and bismuth sulfite agars were unproductive at 32°C but gave quantitative recovery with 48 h of incubation at 22°C. Adjustment of the pH of bismuth sulfite agar to 7.4 made the medium inhibitory. MacConkey, DHL and cefsulodin-irgasan-novobiocin agars gave quantitative recovery with 24 h of incubation at 32°C. Four preenrichment media incubated at four different temperatures, three selective enrichment media incubated at 22°C, and the five plating media were evaluated for their ability to recovery Y. enterocolitica from beef stew seeded with a background of ten other gram-negative bacteria. None of the plating media was superior for recovery; however, cefsulodin-irgasan-novobiocin agar showed the highest confirmation rate for presumptive colonies. Buffered-sorbitol-bile broth was inferior to richer media such as trypticase soy broth for preenrichment. Of the three selective enrichment media examined, only bile-oxalate-sorbose broth was found useful, especially for strains of serotype O:8 which could be recovered after 1 d of preenrichment and 3 d of selective enrichment at 22°C. Strains of serotypes O:8 and O:3 were recovered when two cells with 107 cells of ten other gram-negative bacteria were added to 10 g of beef stew following preenrichment in trypticase soy broth at 2°C for 7 d and selective enrichment in bile oxalate-sorbose broth at 22°C for 3 to 5 d. Strains of serotype O:5,27 were more difficult to recover even with longer enrichment times. These studies indicated that the most comprehensive enrichment system for recovery of Y. enterocolitica from foods is preenrichment in trypticase soy broth at 22°C for 1 d and 2 to 4°C for 4 to 7 d followed by selective enrichment in bile-oxalate-sorbose broth at 22°C for 3 to 5 d and isolation on cefsulodin-irgasan-novobiocin agar.Item Distribution of Exotic Plants in the N. Rocky Mountains by Environmental Type and Disturbance Condition(Montana State Univeristy, 1989-06) Weaver, T.; Gustafson, D.; Lichthardt, J.; Woods, B.This report lists seventy-three exotic species found in a systematic sampling of major environmental zones of the Rocky Mountains between the Canadian border and central Wyoming. For each exotic it states the regional distribution, the environmental types (HTs) it occupies (% constancy), the disturbance conditions (DCs) it occupies (% constancy), and its dominance (in terms of% frequency and% cover) in each cell of the HT x DC matrix. Park managers need to develop policy with respect to legally noxious weeds, forage grasses (eg Phleum pratense, Poa pratensis, Bromus inermis, and Dactylis glomerata), and forage legumes (eg Melilotus and Trifolium spp).Item Cone production in Pinus albicaulis Forests(Inland Mountain West Symposium, 1985-08) Weaver, T.; Forcella, FWhitebark pine cone production was estimated for a 6 to 8 year period in each of 29 stands widespread in.the northern.Rocky Mountains. 1) One-time sampling was possible since the estimate was m2de by multiplying the number of branches perm by an estimate of annual cone production made from counts' of cone lets, mature cones, or cone scars on successively older annual increments of those branches. 2) Average cone production ranged from 0.3 to 3.6 cones·m^-2 ·yr^1 and from 22-270 seeds·m^-2·year^-1 . 3) Regression analysis was used to relate the variance observed to time and place. a) Year-to-year variation in the cone yield of branches, trees, and stands in a region appears to be both internally and externally controlled. Internal control is suggested by the fact that good cone years were usually preceded by poor cone years. While external control is indicated by significant correlations between growth and weather conditions, control is not dominated by the effect of any one factor or any particular developmental stage. b) Although cone production of the average branch varied significantly within 30 percent of the trees and within 48 percent of the stands observed, it did not vary significantly among stands. c) Regressions relating stand cone production to easily measured stand characteristics such as canopy cover, fallen cones, and/or stand size explain no more than 50 percent of the variance among stands.Item Bibliography of Montana vegetation description(1988) Burgeron, P.; Kratz, A.; Weaver, T.; Weidman, N.Listed in alphabetical order by author are 549 references to literature that describes the native vegetation of Montana. This updates the 1965 list of Habeck and Hartley. A keyword subject index is included.Item The selection of native plants for use in the Montana landscape: selection criteria, aesthetic, cultural and environmental evaluation(Montana State University - Bozeman, College of Agriculture, 1985) Bruce, Shelly Marie Engler; Chairperson, Graduate Committee: Richard K. PohlDuring the past 15 years the landscape industry has experienced increased pressure to use native plants as ornamentals. Although a demand for natives in general exists there has been a relunctance on the part of the industry to offer native species because of the economic risks involved. An ornamental scorecard was developed as an evaluation tool for comparing native plant species with plant species currently available on the ornamental market. The scorecard evaluated 24 native Montana plant species and 20 exotic ornamentals commonly used in the landscape industry in Montana. The aesthetic scorecard rated six visual characteristics using color photographs. Scored were form/habit, flower, fruit, bark, leaf, and seasonal characteristics. The thirteen environmental factors evaluated by the environmental scorecard were transplantability, lifespan, propagation, maintenance/cleanliness, soil texture and pH, moisture regime adaptability (both drought and flood tolerance), exposure tolerances (temperature, light, and wind), insect resistance, and disease resistance. Species were scored by a panel of professional evaluators in the botany, horticulture, nursery and landscape design/architecture fields. These scores allow selection of native plant species with visual and/or functional qualities that are of equal or greater value than those exhibited by plants already available on the retail market, and thus exhibit competitive marketing potential.Item Habitat Relations of Mule Deer in the Texas Panhandle.(1985-11-27) Koerth, Benjamin H.; Sowell, Bok F.; Bryant, Fred C.; Wiggers, Ernie P.Telemetric observations of mule deer (Odocoileus hemionus) does were used to determine seasonal relationships between deer use and availability of habitats on two study areas in the Panhandle region of west Texas. Juniper breaks was the only type used in greater proportion than its availability on the Canadian River study area (CRSA). On the Clarendon study area (CSA) mule deer shifted seasonal preferences between riparian, cultivated fields, and juniper breaks. Annual and seasonal home ranges were considerably larger on the CSA. Larger home ranges and variability in seasonal use of the habitat types on the CSA were attributed largely to the presence of cultivated winter grain fields. Shifts in home ranges coincided with the season when production in the cultivated fields was highest and native forage availability was lowest. Comparisons of indirect deer observations (pellet groups and bed sites) with random measurements within each habitat type characterized deer use sites as east and north facing slopes, located close to a canyon rim, and receiving light livestock and human use. The placement of cultivated grain fields could be used to influence overall range use and attract deer to or away from localized sites. Also, consideration should be given to directing heavy livestock and human traffic away from sites that are used by mule deer.Item Horses and Cattle Grazing on the Wyoming Red Desert, III.(1984-03) Plumb, G. E.; Krysl, L. J.; Hubbert, M. E.; Smith, M. A.; Waggoner, J. W.Vegetative cover losses due to trampling near watering sites in the summer and winter are compared for horses grazed alone, cattle grazed alone and horses and cattle grazed in combination. There were significant differences (p<.05) found in the rates of total cover loss as a function of distance to water in both the summer and winter. Grasses sustained heavy trampling losses in all treatments in both seasons. Forbs sustained heavy losses in all treatments during summer. Shrub losses were moderate to low in all treatments during both seasons. Total cover loss was similar in all summer and winter treatments.Item Horses and Cattle Grazing in the Wyoming Red Desert, II. Dietary Quality.(1984-05) Krysl, L. J.; Sowell, Bok F.; Hubbert, M. E.; Plumb, G. E.; Jewett, T. K.; Smith, M. A.; Waggoner, J. W.Botanical composition of horse and cattle diets from fecal analysis and nutrient quality of hand-harvested forages used by these herbivores were evaluated to assess dietary quality during the summer and winter seasons of 1981 in the Wyoming Red Desert. Dietary crude protein estimates averaged 7.5±0.1% and 9.0±0.5% during the summer for horses and cattle, respectively. Dietary crude protein estimates in the winter were lower, averaging 6.1±0% and 6.0±0% for horses and cattle, respectively. Estimated dietary calcium levels for both herbivores were high through the summer and winter, while dietary phosphorus levels appear to be deficient during both seasons. Average in vitro dry matter disappearance coefficients for horses and cattle during the summer were 52±2% and 52±2%, respectively. During the winter these values dropped to 39±1% and 40±1% for horses and cattle, respectively.Item Estimating Digestibility and Faecal Output in Lambs Using Internal and External Markers.(1988-08-01) Krysl, L. J.; Galyean, M. L.; Estell, R. E.; Sowell, Bok F.Twenty fine-wool, ruminally cannulated lambs (average weight 45–9 kg) were used in a completely random design to evaluate the ability of three internal markers to predict dry matter digestibility and two external markers to estimate faecal output. Lambs were allotted randomly to one of four diets: 100% prairie hay (PH), 100% lucerne hay (LH), 50% prairie hay:50% sorghum grain (PS) and 50% lucerne hay: 50% sorghum grain (LS). The trial consisted of a 14-day adaptation period followed by a 7-day total faecal collection period. Feed and faecal samples were subjected to 96 h ruminal fluid and 48 h acid-pepsin digestions, followed by extraction with acid detergent (IVADF) or neutral detergent (IVNDF) solution. Dry matter digestibility (DMD) calculated from feed:faeces ratios of IVADF, IVNDF and acid detergent lignin (ADL) was compared with in vivoapparent digestibility. Ytterbium-labelled forage (YLF) and dysprosium-labelled faeces (DLF) were pulse-dosed via ruminal cannulae, and faecal Yb and Dy excretion curves were fitted to a one-compartment, agedependent model for estimation of faecal output, paniculate passage rate (PPR) and mean gastrointestinal retention time. In vivoDMD in lambs fed PH was greater (P <005) than DMD calculated from IVNDF, IVADF and ADL. In lambs fed LH and LS, in vivoDMD did not differ (P >005) from marker estimates. In vivoDMD for lambs fed PS did not differ from IVNDF or IVADF estimates but was greater than (P <005) the ADL estimate. No differences (P> 005) were observed in recovery among the three internal markers for any of the diets. Faecal output for lambs fed PH did not differ {P >005) from marker estimates but was overestimated by 15 to 20% by YLF and DLF. Faecal output for lambs fed LH was similar to the estimate from YLF, but less than (P <0–05) the estimate with DLF. For lambs fed PS, faecal output did not differ from marker estimates, but YLF and DLF values were 16% lower and 17% higher, respectively. No significant differences were observed in actual and estimated faecal output for lambs fed the LS diet. Estimates of PPR with DLF were numerically greater than YLF estimates for all diets except LS. Correspondingly, mean gastrointestinal retention time was less (P <005) for DLF compared with YLF for all diets except LS.Item Horses and Cattle Grazing in the Wyoming Red Desert(1984-01) Krysl, L. J.; Hubbert, M. E.; Sowell, Bok F.; Plumb, G. E.; Jewett, T. K.; Smith, M. A.; Waggoner, J. W.The sagebrush-grass range in southcentral Wyoming presently supports large numbers of feral horses and domestic livestock. Diets of feral horses and cattle during summer and winter grazing were evaluated using fecal analysis under 2 stocking levels in small pastures. Horses and cattle consumed primarily grasses during the summer and winter. However, shrubs and forbs were also important dietary components. Needleandthread, Sandberg bluegrass, thickspike wheatgrass, Indian ricegrass, gray horsebrush, and winterfat were the major foods of horses and cattle during the summer and winter. Dietary overlap between horses and cattle during the summer averaged 72% and increased to 84% during the winter. Horses and cattle selected foods in a similar order.