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Cattle Ranges of the Southwest: A History of the Exhaustion of the Pasturage and Suggestions for Its Restoration

Description: Report giving "a history of the exhaustion of the pasturage of central Texas, with suggestions for its restoration. The general features of the country are described; the early conditions of the ranges and the causes which have led to their deterioration are graphically portrayed. The obstacles in the way of the improvement of the ranges and how the value of the stock ranges may be renewed are topics discussed in detail. The report closes with brief descriptions of a few other of the most important native grasses and forage plants which may be utilized in improving the pasturage or increasing the production of forage." -- p. 2.
Date: 1898
Creator: Bentley, H. L. (Henry Lewis)
Partner: UNT Libraries Government Documents Department

Impacts of Technology on U.S. Cropland and Rangeland Productivity

Description: A report by the Office of Technology Assessment that "describes the major processes degrading land productivity, assesses whether productivity is sustaining using current agricultural technologies, reviews a range of new technologies with potentials to maintain productivity and profitability simultaneously, and presents a series of options for congressional consideration" (p. iii).
Date: August 1982
Creator: United States. Congress. Office of Technology Assessment.
Partner: UNT Libraries Government Documents Department

Development of range condition classes for Coleman County, Texas

Description: This paper deals with a study of the rangelands in Coleman County just west south and west of the Western Cross Timbers of Texas. This problem consists of classifying certain rangelands in this area according to whether they are excellent, fair, good, or poor, the chief basis for which is their deterioration.
Date: June 1951
Creator: McMinn, Philip Morris
Partner: UNT Libraries

Selective progressive response of soil microbial community to wild oat roots

Description: Roots moving through soil enact physical and chemical changes that differentiate rhizosphere from bulk soil, and the effects of these changes on soil microorganisms have long been a topic of interest. Use of a high-density 16S rRNA microarray (PhyloChip) for bacterial and archaeal community analysis has allowed definition of the populations that respond to the root within the complex grassland soil community; this research accompanies previously reported compositional changes, including increases in chitinase and protease specific activity, cell numbers and quorum sensing signal. PhyloChip results showed a significant change in 7% of the total rhizosphere microbial community (147 of 1917 taxa); the 7% response value was confirmed by16S rRNA T-RFLP analysis. This PhyloChip-defined dynamic subset was comprised of taxa in 17 of the 44 phyla detected in all soil samples. Expected rhizosphere-competent phyla, such as Proteobacteria and Firmicutes, were well represented, as were less-well-documented rhizosphere colonizers including Actinobacteria, Verrucomicrobia and Nitrospira. Richness of Bacteroidetes and Actinobacteria decreased in soil near the root tip compared to bulk soil, but then increased in older root zones. Quantitative PCR revealed {beta}-Proteobacteria and Actinobacteria present at about 10{sup 8} copies of 16S rRNA genes g{sup -1} soil, with Nitrospira having about 10{sup 5} copies g{sup -1} soil. This report demonstrates that changes in a relatively small subset of the soil microbial community are sufficient to produce substantial changes in function in progressively more mature rhizosphere zones.
Date: October 1, 2008
Creator: DeAngelis, K.M.; Brodie, E.L.; DeSantis, T.Z.; Andersen, G.L.; Lindow, S.E. & Firestone, M.K.
Partner: UNT Libraries Government Documents Department

An evaluative study of the grasslands of the R.J. McMurry Ranch, Denton County, Texas

Description: It is the purpose of this problem to classify the four major pastures of the McMurry ranch using the discussed classification system. The definite measurable qualities characterizing each condition of the system are used extensively in this study. The problem is concerned also with the observation of results of misuse, the present practices that could result in further depletion of portions of the McMurry ranch, and procedures being employed at the present time aimed toward the restoration of these depleted portions.
Date: June 1951
Creator: Nolen, Bette Rudd
Partner: UNT Libraries

Wallowa Canyonlands Weed Partnership : Completion Report November 19, 2009

Description: Noxious weeds threaten fish and wildlife habitat by contributing to increased sedimentation rates, diminishing riparian structure and function, and reducing forage quality and quantity. Wallowa Resources Wallowa Canyonlands Partnership (WCP) protects the unique ecological and economic values of the Hells Canyon grasslands along lower Joseph Creek, the lower Grande Ronde and Imnaha Rivers from invasion and degradation by noxious weeds using Integrated Weed Management techniques. Objectives of this grant were to inventory and map high priority weeds, coordinate treatment of those weeds, release and monitor bio-control agents, educate the public as to the dangers of noxious weeds and how to deal with them, and restore lands to productive plant communities after treatment. With collaborative help from partners, WCP inventoried {approx} 215,000 upland acres and 52.2 miles of riparian habitat, released bio-controls at 23 sites, and educated the public through posters, weed profiles, newspaper articles, and radio advertisements. Additionally, WCP used other sources of funding to finance the treatment of 1,802 acres during the course of this grant.
Date: December 30, 2008
Creator: Porter, Mark C. & Ketchum, Sarah
Partner: UNT Libraries Government Documents Department

Detecting vegetation-precipitation feedbacks in mid-Holocene North Africa from two climate models

Description: Using two climate-vegetation model simulations from the Fast Ocean Atmosphere Model (FOAM) and the Community Climate System Model (CCSM, version 2), we investigate vegetation-precipitation feedbacks across North Africa during the mid-Holocene. From mid-Holocene snapshot runs of FOAM and CCSM2, we detect a negative feedback at the annual timescale with our statistical analysis. Using the Monte- Carlo bootstrap method, the annual negative feedback is further confirmed to be significant in both simulations. Additional analysis shows that this negative interaction is partially caused by the competition between evaporation and transpiration in North African grasslands. Furthermore, we find the feedbacks decrease with increasing timescales, and change signs from positive to negative at increasing timescales in FOAM. The proposed mechanism for this sign switch is associated with the different persistent timescales of upper and lower soil water contents, and their interactions with vegetation and atmospheric precipitation.
Date: March 31, 2008
Creator: Wang, Yi; Notaro, Michael; Liu, Zhengyu; Gallimore, Robert; Levis, Samuel & Kutzbach, John E.
Partner: UNT Libraries Government Documents Department

Analysis of the habitat of Henslow's sparrows and Grasshopper sparrows compared to random grassland areas

Description: Henslow's Sparrows are endangered prairie birds, and Grasshopper Sparrows are considered rare prairie birds. Both of these birds were abundant in Illinois, but their populations have been declining due to loss of the grasslands. This begins an ongoing study of the birds habitat so Fermilab can develop a land management plan for the Henslow's and Grasshoppers. The Henslow's were found at ten sites and Grasshoppers at eight sites. Once the birds were located, the vegetation at their sites was studied. Measurements of the maximum plant height, average plant height, and duff height were taken and estimates of the percent of grass, forbs, duff, and bare ground were recorded for each square meter studied. The same measurements were taken at ten random grassland sites on Fermilab property. Several t-tests were performed on the data, and it was found that both Henslow's Sparrows and Grasshopper Sparrows preferred areas with a larger percentage of grass than random areas. Henslow's also preferred areas with less bare ground than random areas, while Grasshoppers preferred areas with more bare ground than random areas. In addition, Grasshopper Sparrows preferred a lower percentage of forbs than was found in random areas and a shorter average plant height than the random locations. Two-sample variance tests suggested significantly less variance for both Henslow's Sparrows and Grasshopper Sparrows for maximum plant height in comparison to the random sites. For both birds, the test suggested a significant difference in the variance of the percentage of bare ground compared to random sites, but only the Grasshopper Sparrow showed significance in the variation in the percentage of forbs.
Date: January 1, 2005
Creator: Maier, Kristen; Walton, Rod; Kasper, Peter & /Fermilab
Partner: UNT Libraries Government Documents Department

Shrub-Steppe Seasons A Natural History of the Mid-Columbia Basin

Description: This book collects and updates a series of articles about the natural history of the Mid-Columbia region. The articles first appeared as a monthly column titled ''Natural History'' in the Tri-City Herald, beginning in May 1991. My approach has been to condense the best of what is known about the ecology of the region to a manageable length with little in the way of technical language and terms. Admittedly, there is a bias toward those topics and species on which I have either been personally involved or observed as part of the ecology research programs conducted on the Fitzner/Eberhardt Arid Lands Ecology (ALE) Reserve. The ALE Reserve is situated on the northeast-facing flank of the Rattlesnake Hills. Rattlesnake Mountain with a crest of over 3,600 feet is visible throughout much of the Mid-Columbia. Shrub-steppe grasslands once covered a large part of the western United States but most have been converted to other uses. The ALE site is the only remaining sizeable acreage (120 square miles) that is in near pristine condition and provides the only clear indication as to what the early trappers, traders, pioneers, and tribal members may have encountered in their day-to-day activities. In this respect, ALE provides a visible touchstone linking the past with the present for all of us.
Date: August 1, 1995
Creator: Rogers, L. E.
Partner: UNT Libraries Government Documents Department

Late archaic settlement systems in the northern Rio Grande

Description: Last year at these meetings I proposed a possible seasonal transhumance pattern for the Late Archaic in the northern Rio Grande region. This pattern involved the movement of groups from the lowland juniper-savanna grasslands in the early summer, to the upland ponderosa pindmixed conifer forests in the mid to late summer, and then back down to the piiion-juniper woodlands during the fall. The Rio Grande Valley was also used for winter habitation sites. Following on this research, I take the next step by studying the inter-assemblage variability represented in a sample of open-air sites located within each of these vegetation communities. The results indicate that there are significant differences in reduction tactics represented between valley habitation vs., upland campsites, and that these site sites are linked together by obsidian procurement patterns.
Date: January 1, 2003
Creator: Vierra, Bradley J.
Partner: UNT Libraries Government Documents Department

Aspen Ecology in Rocky Mountain National Park: Age Distribution, Genetics, and the Effects of Elk Herbivory

Description: Lack of aspen (Populus tremuloides) recruitment and canopy replacement of aspen stands that grow on the edges of grasslands on the low-elevation elk (Cervus elaphus) winter range of Rocky Mountain National Park (RMNP) in Colorado has been a cause of concern for more than 70 years (Packard, 1942; Olmsted, 1979; Stevens, 1980; Hess, 1993; R.J. Monello, T.L. Johnson, and R.G. Wright, Rocky Mountain National Park, 2006, written commun.). These aspen stands are a significant resource since they are located close to the park's road system and thus are highly visible to park visitors. Aspen communities are integral to the ecological structure of montane and subalpine landscapes because they contain high native species richness of plants, birds, and butterflies (Chong and others, 2001; Simonson and others, 2001; Chong and Stohlgren, 2007). These low-elevation, winter range stands also represent a unique component of the park's plant community diversity since most (more than 95 percent) of the park's aspen stands grow in coniferous forest, often on sheltered slopes and at higher elevations, while these winter range stands are situated on the low-elevation ecotone between the winter range grasslands and some of the park's drier coniferous forests.
Date: October 1, 2008
Creator: Tuskan, Gerald A & Yin, Tongming
Partner: UNT Libraries Government Documents Department

Habitat Evaluation Procedures (HEP) Report; Calispell Creek Project, Technical Report 2004-2005.

Description: On July 13, 2004, the Habitat Evaluation Procedure (HEP) was used to determine baseline habitat suitability on the Calispell Creek property, an acquisition completed by the Kalispel Tribe of Indians in February 2004. Evaluation species and appropriate models include Canada goose, mallard, muskrat, yellow warbler, and white-tailed deer. Habitat Suitability Index (HSI) values were visually estimated and agreed upon by all HEP team members. The Calispell Creek Project provides a total of 138.17 Habitat Units (HUs) for the species evaluated. Emergent wetland habitat provides 5.16 HUs for mallard and muskrat. Grassland provides 132.02 HUs for mallard and Canada goose. Scrub-shrub vegetation provides 0.99 HUs for yellow warbler and white-tailed deer. The objective of using HEP at the Calispell Creek Project and other protected properties is to document the quality and quantity of available habitat for selected wildlife species. In this way, HEP provides information on the relative value of the same area at future points in time so that the effect of management activities on wildlife habitat can be quantified. When combined with other tools, the baseline HEP will be used to determine the most effective on-site management, restoration, and enhancement actions to increase habitat suitability for targeted species. The same process will be replicated every five years to quantitatively evaluate the effectiveness of management strategies in improving and maintaining habitat conditions while providing additional crediting to BPA for enhanced habitat values.
Date: February 1, 2005
Creator: Entz, Ray
Partner: UNT Libraries Government Documents Department

Habitat Evaluation Procedures (HEP) Report : Priest River, 2004-2005 Technical Report.

Description: On July 6, 2004, the Habitat Evaluation Procedure (HEP) was used to determine baseline habitat suitability on the Priest River property, an acquisition completed by the Kalispel Tribe of Indians in 2001. Evaluation species and appropriate models include bald eagle, black-capped chickadee, Canada goose, mallard, yellow warbler, and white-tailed deer. Habitat Suitability Index (HSI) values were visually estimated and agreed upon by all HEP team members. The Priest River Project provides a total of 105.41 Habitat Units (HUs) for the species evaluated. Conifer forest habitat provides 26.95 HUs for bald eagle, black-capped chickadee, and white-tailed deer. Grassland habitat provides 23.78 HUs for Canada goose and mallard. Scmb-shrub vegetation provides 54.68 HUs for mallard, yellow warbler, and white-tailed deer.
Date: February 1, 2005
Creator: Entz, Ray
Partner: UNT Libraries Government Documents Department

Precipitation and soil impacts on partitioning of subsurface moisture in Avena barbata: Observations from a greenhouse experiment

Description: The primary objective of this study was to assess the impact of two grassland soils and precipitation regimes on soil-moisture dynamics. We set up an experiment in a greenhouse, and monitored soil moisture dynamics in mesocosms planted with Avena barbata, an annual species found in California grasslands. By repeating the precipitation input at regular intervals, we were able to observe plant manipulation of soil moisture during well-defined periods during the growing season. We found that the amount of water partitioned to evapotranspiration, seepage, and soil storage varied among different growth stages. Further, both soil type and precipitation regimes had a significant impact on redistributing soil moisture. Whereas in the low-precipitation treatments most water was released to the atmosphere as evapotranspiration, major losses from the high-precipitation treatment occurred as gravity drainage. Observations from this study emphasize the importance of understanding intra-seasonal relationships between vegetation, soil, and water.
Date: March 1, 2011
Creator: Salve, R. & Torn, M.S.
Partner: UNT Libraries Government Documents Department

Perennial grasses for energy and conservation: Evaluating some ecological agricultural, and economic issues

Description: Perennial prairie grasses offer many advantages to the developing biofuels industry. High yielding varieties of native prairie grasses such as switchgrass, which combine lower levels of nutrient demand, diverse geographical growing range, high net energy yields and high soil and water conservation potential indicate that these grasses could and should supplement annual row crops such as corn in developing alternative fuels markets. Favorable net energy returns, increased soil erosion prevention, and a geographically diverse land base that can incorporate energy grasses into conventional farm practices will provide direct benefits to local and regional farm economies and lead to accelerated commercialization of conversion technologies. Displacement of row crops with perennial grasses will have major agricultural, economic, sociologic and cross-market implications. Thus, perennial grass production for biofuels offers significant economic advantages to a national energy strategy which considers both agricultural and environmental issues.
Date: November 1, 1995
Creator: Downing, M.; Walsh, M. & McLaughlin, S.
Partner: UNT Libraries Government Documents Department

Ground-based grasslands data to support remote sensing and ecosystem modeling of terrestrial primary production

Description: Estimating terrestrial net primary production (NPP) using remote- sensing tools and ecosystem models requires adequate ground-based measurements for calibration, parameterization, and validation. These data needs were strongly endorsed at a recent meeting of ecosystem modelers organized by the International Geosphere-Biosphere Programme`s (IGBP`s) Data and Information System (DIS) and its Global Analysis, Interpretation, and Modelling (GAIM) Task Force. To meet these needs, a multinational, multiagency project is being coordinated by the IGBP DIS to compile existing NPP data from field sites and to regionalize NPP point estimates to various-sized grid cells. Progress at Oak Ridge National Laboratory (ORNL) on compiling NPP data for grasslands as part of the IGBP DIS data initiative is described. Site data and associated documentation from diverse field studies are being acquired for selected grasslands and are being reviewed for completeness, consistency, and adequacy of documentation, including a description of sampling methods. Data are being compiled in a database with spatial, temporal, and thematic characteristics relevant to remote sensing and global modeling. NPP data are available from the ORNL Distributed Active Archive Center (DAAC) for biogeochemical dynamics. The ORNL DAAC is part of the Earth Observing System Data and Information System, of the US National Aeronautics and Space Administration.
Date: December 31, 1995
Creator: Olson, R.J.; Turner, R.S.; Scurlock, J.M.O. & Jennings, S.V.
Partner: UNT Libraries Government Documents Department

The Overland Cattle Trade

Description: One of the most fascinating subjects in all American history is the story of the great cow country. Its heyday was the twenty-year period from 1868 to 1888. It extended from below the Rio Grande on the south to well up in Saskatchewan in western Canada on the north. East and west it reached from the Rocky Mountains to about the Missouri- Arkansas border. It occupied a region nearly 2,000 miles long and from 200 to 700 miles wide--almost a million square miles in one vast open range. For countless years this region had been the home of millions of wild buffaloes, but in a very short time after 1868 it was transformed into a gigantic cattle kingdom. After two decades of spectacular existence, it just as suddenly passed away, and the cattle industry entered a new and in many ways an entirely different era. Texas cattle and Texas cattlemen played leading roles in this great drama of the West. The warm southern plains of Texas were the breeding place-the "incubator"-f or thousands of longhorn cattle, the broad prairies to the north were their feeding grounds, and the newly established railroad towns in Kansas and other states were the shipping points.
Date: August 1952
Creator: Massey, Travis Leon
Partner: UNT Libraries