Rangelands Of Idaho Research Articles

Grazing behavior and production characteristics among cows differing in residual feed intake while grazing late season Idaho rangeland.

The objectives were to determine whether cows previously classified during a postweaning test as either low or high residual feed intake (LRFI or HRFI) differed in BW, BCS, and winter grazing activity while consuming poor-quality forage. Thirty Hereford × Angus (LRFI = 16; HRFI = 14) 2-yr-old mid- to late-gestation cows (pregnant with second calf) grazed sagebrush steppe for 78 d beginning 29 September 2015. BW and BCS were collected before and after grazing. Five cows of each RFI classification were fitted with global positioning system (GPS) collars on 16 November 2015 with data collection commencing 3 d later and continuing for 25 d in a 323-ha pasture. The GPS units collected location coordinates every 2 min from which total daily travel distance (DTD) was calculated. Visual counts for bite rate were obtained from collared cows over 8 d. Coordinate data, daily bite rate, BW, and BCS were analyzed as repeated measures using a mixed model, which included RFI group, day, and RFI group × day as fixed effects and cow within RFI group as the random effect. Change in BW and BCS was analyzed by ANOVA with RFI group as the main effect. Cow BCS and BW differed for both day (P < 0.0001) and day × RFI (P < 0.05). Body condition was less (P < 0.05) in LRFI cows at the beginning (5.8 ± 0.13 vs. 6.2 ± 0.14 BCS), but similar (P = 0.67) to HRFI at the end of the study (4.6 ± 0.13 vs. 4.6 ± 0.14). BW among the RFI groups did not differ (P = 0.20) prior to going to range. However, BW-change and BCS-change differed (P < 0.05) between RFI groups. Not only did the LRFI cows lose less BW (-50.0 ± 5.41 kg vs. -66.6 ± 5.78 kg) over the trial, they also were less variable with respect to BW loss. Cows did not differ (P > 0.21) by RFI for DTD or bite rate, but day was significant (P < 0.0001) with cows increasing bite rate as the season of year progressed (55.2 ± 5.63 bites/min for day 4 vs. 84.8 ± 5.32 bites/min for day 21) and increasing DTD as snow storms occurred. Although LRFI cows were leaner than HRFI cows at the commencement of the project, they lost less BW in a late season rangeland environment.

PSI-23 In vitro fermentation characteristics for Cheatgrass (Bromus tectorum L.) and Medusahead (Taeniatherum caputmedusae L.) harvested on Idaho rangeland in different seasons

Abstract Grazing could be used to control invasive grass species on rangeland. However, the characterization of the seasonal changes in the nutritive value of the invasive grass species will enable the development of targeted grazing strategies. Therefore, the objective of this study was to determine the in vitro fermentation characteristics of Cheatgrass (Bromus tectorum L.) and Medusahead (Taeniatherum caputmedusae L.) harvested on Idaho rangeland. Forage samples were collected from the Reynold Creek watershed (Owyhee county, ID) in summer (June 2018), fall (September 2018) and winter (January 2019). A batch culture system was then used to evaluate volatile fatty acid (VFA) production (6 h), and in vitro dry matter (IVDMD) and NDF digestibility (IVNDFD; 24 h and 48 h). All data was analyzed using the MIXED procedure of SAS. There was no season or grass species effect (P ≥ 0.24) on total VFA concentration and the molar proportion of acetate. However, there was a season × grass species interaction (P = 0.04) for the molar proportion of propionate; it was higher for cheatgrass than medusahead in summer, but not in winter and fall. Both season and grass species had no effect (P ≥ 0.11) on the molar proportions of butyrate, valerate, and total branch chain VFA. There was a season × grass species interaction for 24 and 48 h IVDMD and 24 h IVNDFD (Table 1). In addition, 48 h IVNDFD was greater (P &amp;lt; 0.01) when grasses were harvested during the summer compared to the fall and winter seasons. In summary, although there were no differences across invasive grass species when harvested during the fall and winter seasons, the molar proportion of propionate, 24 and 48 h IVDMD and 24 h IVNDFD were greater for cheatgrass compared to medusahead when harvested in summer.

Restoring Perennial Grasses in Medusahead Habitat: Role of Tilling, Fire, Herbicides, and Seeding Rate

Restoring arid regions degraded by invasive annual grasses to native perennial grasses is a critical conservation goal. Targeting site availability, species availability, and species performance is a key strategy for reducing invasive annual grass cover while simultaneously increasing the abundance of seeded native perennial grasses. However, the potential for establishing successful seedings is still highly variable in rangeland ecosystems, likely because of variable year-to-year weather. In this study, we evaluated the independent and combined inputs of tilling, burning, applying imazapic herbicide, and varying seeding rates on existing species and seeded native perennial grass performance from 2008 to 2012 in a southwestern Idaho rangeland ecosystem. We found that combining tilling, fire, and herbicides produced the lowest annual grass cover. The combination of fire and herbicides yielded the highest seeded species density in the hydrologic year (HY) (October−September) 2010, especially at higher than minimum recommended seeding rates. Although the independent and combined effects of fire and herbicides directly affected the growth of resident species, they failed to affect seeded species cover except in HY 2010, when weather was favorable for seedling growth. Specifically, low winter temperature variability (few freeze-thaw cycles) followed by high growing season precipitation in HY 2010 yielded 14× more seeded perennial grasses than any other seeding year, even though total annual precipitation amounts did not greatly vary between 2009 and 2012. Collectively, these findings suggest that tilling, applying prescribed fire, and herbicides before seeding at least 5× the minimum recommended seeding rate should directly reduce resident annual grass abundance and likely yield high densities of seeded species in annual grass−dominated ecosystems, but only during years of stable winter conditions followed by wet springs.

0062 WS Grazing behavior and production characteristics among cows differing in residual feed intake while grazing late season Idaho rangeland

0062 WS Grazing behavior and production characteristics among cows differing in residual feed intake while grazing late season Idaho rangeland

Assessing the impact of seasonal precipitation and temperature on vegetation in a grass-dominated rangeland

Changes in vegetation are affected by many climatic factors and have been successfully monitored through satellite remote sensing over the past 20 years. In this study, the Normalised Difference Vegetation Index (NDVI), derived from the Moderate Resolution Imaging Spectroradiometer (MODIS) onboard the Terra satellite, was selected as an indicator of change in vegetation. Monthly MODIS composite NDVI at a 1-km resolution was acquired throughout the 2004–09 growing seasons (i.e. April–September). Data describing daily precipitation and temperature, primary factors affecting vegetation growth in the semiarid rangelands of Idaho, were derived from the Surface Observation Gridding System and local weather station datasets. Inter-annual and seasonal fluctuations of precipitation and temperature were analysed and temporal relationships between monthly NDVI, precipitation and temperature were examined. Results indicated NDVI values observed in June and July were strongly correlated with accumulated precipitation (R2 &gt;0.75), while NDVI values observed early in the growing season (May) as well as late in the growing season (August and September) were only moderately related with accumulated precipitation (R2 ≥0.45). The role of ambient temperature was also apparent, especially early in the growing season. Specifically, early growing-season temperatures appeared to significantly affect plant phenology and, consequently, correlations between NDVI and accumulated precipitation. It is concluded that precipitation during the growing season is a better predictor of NDVI than temperature but is interrelated with influences of temperature in parts of the growing season.

Assessing the Success of Postfire Reseeding in Semiarid Rangelands Using Terra MODIS

Successful postfire reseeding efforts can aid rangeland ecosystem recovery by rapidly establishing a desired plant community and thereby reducing the likelihood of infestation by invasive plants. Although the success of postfire remediation is critical, few efforts have been made to leverage existing geospatial technologies to develop methodologies to assess reseeding success following a fire. In this study, Terra Moderate Resolution Imaging Spectroradiometer (MODIS) satellite data were used to improve the capacity to assess postfire reseeding rehabilitation efforts, with particular emphasis on the semiarid rangelands of Idaho. Analysis of MODIS data demonstrated a positive effect of reseeding on rangeland ecosystem recovery, as well as differences in vegetation between reseeded areas and burned areas where no reseeding had occurred (P,0.05). We conclude that MODIS provides useful data to assess the success of postfire reseeding.

Idaho Rangeland Resource Commission: Commitment to Rangeland Education

Idaho is proud to co-host the 2012 SRM Annual Meeting. Rangelands are integral to the customs, culture, and economy of Idaho; nearly half of Idaho is rangeland. Eighty percent of the rangelands in Idaho are public lands administered by federal and state agencies. Consequently, public perceptions and associated public land policies have a profound influence on the use and management of Idaho The Idaho Rangeland Resource Commission (IRRC) is uniquely charged with educating the public on the responsible management of Idaho's rangelands. In 1994, the Idaho legislature created the IRRC in response to the enthusiastic support of both livestock producers and rangeland managers throughout Idaho. The expressed objec tives of this commission are to encourage sustainable range land management practices and to provide objective, proactive, educational programs about rangeland manage ment to the citizens of Idaho. The IRRC is governed by a board of directors whose members are appointed by the Governor for a maximum of two consecutive, 5-year terms.1

Herbaceous Biomass Estimation from SPOT 5 Imagery in Semiarid Rangelands of Idaho

Eight vegetation indices (VI) commonly used for above-ground biomass (AGB) estimation were derived from Satellite Pour l'Observation de la Terre 5 (SPOT 5) imagery and used to predict herbaceous AGB at a semiarid rangeland study site in southeastern Idaho. The relationship between herbaceous AGB and vegetation water content was also evaluated and as a result, a suite of water-sensitive vegetation indices (WSVI) were developed. Correlation coefficients between herbaceous AGB, VIs, and WSVIs were calculated, demonstrating that WSVIs were correlated (r 2 ≥ 0.51) with vegetation water content and performed better than standard VIs in herbaceous AGB estimates within the semiarid rangelands of Idaho.

Idaho Rangeland Resource Commission: Commitment to Rangeland Education

Idaho Rangeland Resource Commission: Commitment to Rangeland Education

Comparison of MODIS fPAR Products with Landsat-5 TM-Derived fPAR over Semiarid Rangelands of Idaho

While validation of the MODIS fPAR product is well behind that of the LAI product, it is recently receiving more attention. In this study, MODIS fPAR and Landsat-5 TM-derived fPAR (TM fPAR) were calculated and quantitatively compared using imagery from 2005 to 2008 for the semiarid rangelands of Idaho, USA. fPAR change maps were calculated between active growth and late-summer senescence periods. Accuracy of the MODIS fPAR and TM fPAR were determined indirectly by incorporating field-based measurements of above-ground forage biomass and percent ground cover from a variety of sites (n = 442).

Southern Idaho Student “Bug Crews”: Weeds, youth, and biocontrol in the rangelands of Idaho

Southern Idaho Student “Bug Crews”: Weeds, youth, and biocontrol in the rangelands of Idaho DOI:10.2458/azu_rangelands_v31i3_Gunderson

Southern Idaho Student “Bug Crews”: Weeds, youth, and biocontrol in the rangelands of Idaho

Southern Idaho Student “Bug Crews”: Weeds, youth, and biocontrol in the rangelands of Idaho

Southern Idaho Student “Bug Crews”: Weeds, youth, and biocontrol in the rangelands of Idaho

Southern Idaho Student “Bug Crews”: Weeds, youth, and biocontrol in the rangelands of Idaho

Assessing the economic impact of invasive species: The case of yellow starthistle ( Centaurea solsitialis L.) in the rangelands of Idaho, USA

Yellow starthistle ( Centaurea solsitialis L.) is an invasive weed that creates problems for the management of Idaho's rangelands. A bioeconomic approach combined with an input–output economic model is used to estimate direct and secondary economic costs of the weed in relation to its interference with agricultural and non-agricultural benefits that rangelands provide. Direct economic costs of the infestations were estimated to be of 8.2 million ‘05 dollars per year, and secondary costs of 4.5 million ‘05 dollars per year, for a total of 12.7 million ‘05 dollars; agricultural related economic impacts accounted for 79% of this total cost, and non-agricultural for 21%.

Spatial analysis of grasshopper density and ecological disturbance on southern Idaho rangeland

Historical grasshopper survey data were used to relate grasshopper densities to ecological condition classes on the Bureau of Land Management's Shoshone District in Idaho as part of an effort to identify areas prone to high grasshopper densities and to understand the effects of range management practices on grasshopper populations. A MOSS-based Geographic Information System was used to overlay maps of ecological condition, elevation, and grasshopper density to test the hypothesis that grasshopper density was the same for all ecological condition classes. Areas that had been severely disturbed by wildfires and invasion of exotic annual vegetation had significantly higher grasshopper densities over the 3 years examined than less severely disturbed area that retained some sagebrush cover. This suggests that shrub loss due to wildfires or other causes may lead to greater grasshopper densities. The techniques and applicability of geostatistical spatial analysis to these questions is also discussed.

Forage Yield and Quality in a Great Basin Shrub, Grass, and Legume Pasture Experiment

A study was conducted in central Utah to determine the forage and protein yield relationships among the components of grassshrub-legume plantings in a semiarid rangeland pasture. Forage and protein yields of crested wheatgrass (Agropyron cristatum) and total herbage increased when fourwing saltbush shrubs (Atripkx canescens) or legumes (Astragalus cicer, A. fakatus, or Medicage sativa) were grown in association. The shrub and legume species directly contributed to the increase in these yields and to more rapid regrowth of crested wheatgrass. Rehabilitation of depleted rangelands in the United States has received much research attention since the mid 1930’s. This has guided successful seeding of several million hectares throughout the West. Seeding emphasis was on grasses and only a little attention was given to forbs and almost none to shrubs (Blaisdelll972). The two crested wheatgrasses, standard crested wheatgrass (Agropyron desertorum) and ‘Fairway’ crested wheatgrass (Agropyron cristarum), were most commonly seeded. Fairway crested wheatgrass can grow on dry sites where few other grasses survive (Plummer et al. 1968). It isa preferred species for inclusion in mixtures with other grasses, forbs, and shrubs. Dubbs (1966) found that Fairway crested wheatgrass was more palatable than standard crested wheatgrass over a longer part of the year. Neither sheep nor heifers liked standard crested wheatgrass after heading. Fairway was leafier than standard crested wheatgrass but no higher in protein content. Fourwing saltbush (Atriplex canescens) is a native, dioecious shrub that occurs on desert and foothill ranges in western America and has been included in some range plantings. It grows to heights of 60 to 180 cm with most of the seasonal growth in midsummer. This shrub was reported to be one of the most abundant producers of forage and seed tested on Utah game ranges (Plummer et al. 1968). Springfield (1966) considered it to be a useful shrub for ranges of southwestern United States. Palatability of fourwing saltbush forage to sheep was intermediate between prostrate summer cypress (Kochia prostrata) and Artemisia herba alba in Iran where it was considered a promising forage plant for large scale plantings (Nemati 1977). Monsen (1980) successfully interseeded fourwing saltbush and crested wheatgrass into southern Idaho rangelands dominated by sagebrush (Artemisia spp.)and an annual grass. The presence of the saltbush shrubs did not reduce the grass density or herbage yields. Cattle readily accepted the saltbush as a forage species and utilized approximately 50% of the annual growth. A number of legume species have been suggested for use in range renovation programs. Townsend et al. (1975) tested 14 legumes and concluded that cicer chickpea milkvetch (Astragalus cicer), sicklepod milkvetch (Astragalus falcatus), and alfalfa (Medicugo sutiva) merited additional evaluation for potential use under dryland or range conditions. Cicer milkvetch was considered adapted

Bottom Sediment: A Reservoir of Escherichia coli in Rangeland Streams

Escherichia coli concentrations of bottom sediment and overlying water were determined from a variety of streams in southwestern Idaho by a one-step most probable number technique. Results show E. coli concentrations of bottom sediments to be from 2 to 760 times greater than from the overlying water. E. coliconcentrations of bottom sediment were found to be resuspended following disturbance simulation and a rainstorm event, contributing to pollution of the overlying waters. It is, therefore, suggested that microbial analysis of bottom sediments be considered a part of water-quality evaluations for rangeland streams. During the past decade, Federal legislative action has brought attention to sources of nonpoint pollution related to livestock grazing on public lands. Collectively, the National Environmental Policy Act of 1969, the Federal Water Pollution Control Act Amendments of 1972, and the Federal Land Policy and Management Act of 1976 have specified the need to establish criteria for identifying pollution sources and to improve environmental quality of streams through improved management. To achieve the goals set forth in these acts, many research programs have been initiated to identify and document pollution sources. One of the findings has been the implication that livestock grazing on western rangeland watersheds is a source of bacterial pollution of streams (Darling and Coltharp 1973; Doty and Hookano 1974; Buckhouse and Gifford 1976; Skinner et al. 1974; Authors are geologist, USDA ARS, 1175 South Orchard, Suite 116, Boise, Idaho 83705; and associate professor of microbiology, Boise State University, 1910 University Drive, Boise, Idaho 83725, respectively. This research is a contribution from the Northwest Watershed Research Center, Agricultural Research Service, U.S. Dep. Agr.; and Bureau of Land Management, U.S. Dep. Interior; in cooperation with the Agricultural Experiment Station, University of Idaho, Moscow 83843. The authors gratefully acknowledge the efforts of James Harris and Rebecca O'Brien, biological technicians, for their laboratory and field assistance during the course of this study. Manuscript received May 27, 1980. Stephenson and Street 1978). Researchers have had difficulty, however, explaining variations in bacterial indicators occurring in many of the studies (Buckhouse and Gifford 1976; Darling and Coltharp 1973; Kunkle 1970; Skinner et al. 1974; Stephenson and Street 1978). These variations can be characterized by two questions: (1) why do fecal coliform counts remain relatively high in some streams after livestock have been removed from the area, and (2) what is the source of sudden fecal coliform increases in stream runoff from rainstorms or snowmelt? Wildlife have been suggested as the source in question one (Fair and Morrison 1967; Stuart et al. 1971; Walter and Bottman 1967; Doran and Linn 1979), while for question two, Stephenson and Street (1978) suggest that fecal coliforms remain in soil and adjacent streambanks to be flushed into the streams during subsequent runoff. In an attempt to more fully answer the above questions, we began a study in 1979 on southwestern Idaho rangeland, utilizing eight sampling sites on six separate shallow stream segments within varying land-use practices. Our objective was to evaluate stream bottom sediments as a possible reservoir of bacterial pollutants available to overlying surface waters via resuspension. In previous work relating possible bacterial pollutants to stream bottom sediment, none of the studies have dealt with rangeland environments. In a study of the Greenwater River Watershed in Washington, Varness et al. (1978) found that concentrations of fecal coliforms increased dramatically during periods of human use. Since rainfall and surface runoff were minimal, they suggested that fecal coliforms might be surviving in sediments. Matson et al. (1978) found mean fecal coliform counts in sediment to be 2,500 times greater than in the overlying water, upstream of a sewage treatment plant on the Shetucket River in northeastern Connecticut. Downstream of the treatment plant effluent discharge site, the fecal coliform counts for the sediment JOURNAL OF RANGE MANAGEMENT 35(1), January 1982 119 This content downloaded from 207.46.13.33 on Sun, 20 Nov 2016 04:17:32 UTC All use subject to http://about.jstor.org/terms Boise P?j 2 ~~Idaho City

Broadcast Burning of Sagebrush in the Winter

Table 1. Sagebrush stand characteristics of the mean, range, and Sagebrush-grass vegetation occupies about 5.5 million hectares of Idaho rangelands. Rangeland productivity has decreased as presettlement sagebrush densities have increased. Prescribed burning of such rangeland has proven to be an efficient and economic tool to reclaim sagebrush- dominated areas, but firing techniques and weather prescriptions for fire use have not been developed. Feasibility of winter burning with snow or ice on the surface of the soil was tested with the following restrictions: (1) sagebrush was dense, with a canopy cover about 50%, and (2) distance between plants cannot exceed 50% of their average height. With these restrictions, fire carried through sagebrush canopies when effective wind speed was above 8 km/hr (5 mph) and winter ignition index was Y,r29. Under the above prescription, only small areas burned. Winter burning might be impractical in most areas because of imposed stand limitations and the 10~ number of days with proper burning conditions. However, winter broadcast burning is possible, inexpensive, and completely safe when snow or ice is present, and requires no fire control preparation or mop-up. coefficient of variation (c.v.) is based from 250 samples.

Bacterial Variations in Streams from a Southwest Idaho Rangeland Watershed

AbstractSources and variations in bacterial indicators are reported from stream sites over a 3‐year period on a 233‐km2 rangeland watershed in southwest Idaho. The occurrence of fecal coliforms was directly related to the presence of cattle on summer range and winter pastures. Fecal coliform counts in adjacent streams were found to increase soon after cattle were turned in and remained high for several months after cattle were removed.Runoff from rainstorms increased both total and fecal coliform concentrations in streams on summer range with limited management and adjacent to winter pastures, but runoff from snowmelt had little effect. Total coliform counts varied more with change in streamflow than did fecal coliform counts. In fenced summer range allotments, under deferred grazing management, the effects were the same, except bacterial counts were not as high or persistent.The decrease in bacterial concentrations at several downstream sampling sites indicated that certain stream segments were self‐purifying. The presence or absence of livestock along the streams overshadow any effect variations in chemical concentration of the water might have on bacterial concentrations.

Mechanical Control and Fertilization as Brush Management Practices Affect Forage Production in South Texas

LITERATURE CITED HULL, A. C., JR. 1954. Rating seeded stands on experimental range plots. J. Range Manage. 7:122-124. HULL, A. C., JR. 1959. Pellet seeding of wheatgrasses on southern Idaho rangelands. J. Range Manage. 12: 155-163. HULL, A. C., JR., AND G. J. KLOMP. 1966. Longevity of crested wheatgrass in the sagebrush-grass type in southern Idaho. J. Range Manage. 19:5-11. WEINTRAUB, FRANCIS. 1953. Grasses introduced into the United States. U. S. Dep. Agr. Handbook 58. 79 p.