Life Sciences Commons^™

Temporal Changes In The Nutrient Content Of Cattle Dung In The Nebraska Sandhills Ecosystem, Amanda Shine, Martha Mamo, Gandura O. Abagandura, Walter Schacht, Jerry Volesky

Department of Agronomy and Horticulture: Faculty Publications

Dung excreted by cattle composes a significant portion of the nutrient inputs in a grazed ecosystem and can have wide-ranging effects on soil properties and vegetation. However, little research has been conducted on the nutrient dynamics of excreted dung in situ that has not been disturbed prior to field sampling. In this study, we analyzed 294 dung pats (1–24 days old) collected from a Nebraska Sandhills meadow to determine water-extractable organic carbon (WEOC), water-extractable nitrogen (WEN), water-extractable phosphorus (WEP), and percent dry matter (DM) changes over time. In addition, we investigated if sample handling - frozen storage – and the …

Does Integrating Crops With Livestock Production Impact Soil Properties And Crop Production?, Lindsey Anderson

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Re-integrating crop and livestock production through cover crop (CC) and corn residue grazing could efficiently utilize resources and ensure profitability while improving environmental quality, but how this integration affects soils and crops is not well understood. We conducted two studies to address this. In the first study, we evaluated the impact of cattle (1.3-3.7 head ha^-1) grazing an oat (Avena sativa L.) CC on soil and crop yields in two adjacent irrigated no-till corn (Zea mays L.)-soybean (Glycine max L.) fields on silt loam soils in eastern Nebraska. Field I was grazed twice, while Field …

Spring Meadow Management Practices: What’S A Rancher To Do?, Tara M. Harms, Jerry D. Volesky, Mitchell B. Stephenson

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

• Subirrigated meadows are a valuable forage resource to ranching operations in the Nebraska Sandhills, being used for both hay production and livestock grazing. • The water table of these meadows is within one meter of the soil surface during the growing season. • In some years, wet conditions hinder meadow utilization, resulting in a buildup of standing dead and litter plant material which can lower forage production.

• Investigate if burning and mowing are effective strategies to remove dead plant material from meadows • Determine if burning or mowing interact with grazing to influence end of season forage production …

Use Of Uav Imagery And Nutrient Analyses For Estimation Of The Spatial And Temporal Contributions Of Cattle Dung To Nutrient Cycling In Grazed Ecosystems, Amanda Shine

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Nutrient inputs from cattle dung are crucial drivers of nutrient cycling processes in grazed ecosystems. These inputs are important both spatially and temporally and are affected by variables such as grazing strategy, water location, and the nutritional profile of forage being grazed. Past research has attempted to map dung deposition patterns in order to more accurately estimate nutrient input, but the large spatial extent of a typical pasture and the tedious nature of identifying and mapping individual dung pats has prohibited the development of a time- and cost-effective methodology. The first objective of this research was to develop and validate …

Grazing Strategy Effects On Utilization, Animal Performance, Aboveground Production, Species Composition, And Soil Properties On Nebraska Sandhills Meadow, Aaron Shropshire

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Ultrahigh stocking density (a.k.a., mob grazing) is proposed as a management tool that results in greater harvest efficiency, animal performance, aboveground plant production, species richness, and soil carbon content. The study objective was to determine grazing treatment, haying, or non-defoliated control effects on forage utilization, aboveground production, animal performance, and soil properties. In 2010, 25 ha of Sandhills meadow were divided into 2 replications of 3 grazing, a hay, and control treatment. Grazing treatments were a 120-pasture rotation with one grazing cycle (mob), a 4-pasture rotation with one cycle (4PR1), and a 4-pasture rotation with two cycles (4PR2) at stocking …

Invasion During Extreme Weather: Success And Failure In A Temperate Perennial Grassland, James C. Han, Stephen L. Young

West Central Research and Extension Center, North Platte

Invasive and native plant species compete for resources in similar pools, with disturbances often favoring the invader. Yet, increased climate variability may be shifting the competitive edge back toward the natives. We conducted field studies in perennial grasslands to determine the effects of clipping and drought on resource availability (light and moisture) and subsequent establishment of Carduus nutans. We measured light penetration and soil moisture content in C. nutans monoculture, clipped and non clipped grassland with C. nutans, and bare ground control plots. We also tracked phenology of the invader and grasses. Our studies revealed that light was a limiting …

Corn Residue Stocking Rate Affects Cattle Performance But Not Subsequent Grain Yield, L. A. Stalker, H. Blanco-Canqui, Jennifer A. Gigax, A. L. Mcgee, T. M. Shaver, S. J. Van Donk

West Central Research and Extension Center, North Platte

This study investigated effects of stocking rate on cattle performance, quality and quantity of corn residue, and impact of residue removal on grain yield for 5 yr at the University of Nebraska – Lincoln West Central Water Resources Field Laboratory near Brule, NE. Four removal treatments—1) no removal (control), 2) grazing at 2.5 animal unit month (AUM)/ ha, 3) grazing at 5.0 AUM/ha, and 4) baling—were applied to a center pivot–irrigated corn field (53 ha). The field was divided into eight 6.6-ha paddocks to which replicated treatments were assigned. Samples of residue were collected in October and March (before and …

Changes In Corn Residue Quality Throughout The Grazing Period And Effect Of Supplementation Of Calves Grazing Corn Residue, Amanda J. Burken

Department of Animal Science: Dissertations, Theses, and Student Research

Corn residue is an abundant feed source in Nebraska that can be utilized as an alternative winter feed. Calves were backgrounded on corn residue in order to determine gain and estimate forage intake when supplemented with distillers grains (DGS). Calves grazing the non-irrigated field gained more (1.03 kg/calf daily) when compared to those grazing the irrigated field (0.90 kg/calf daily; P < 0.01). In year 1, a quadratic effect for intake of DGS was present (P < 0.01) while year 2 observed a linear effect for increasing level of DGS (P < 0.01). The nutritional quality of corn residue was evaluated over time in order to determine changes in blade/sheath, cob, husk/shank and stem. Minimal changes in DM of the forage components occurred was grain reached 15.5% moisture. Digestibility of the blade/sheath declined linearly over time (P < 0.01) while the husk remained constant (P = 0.40). Cob digestibility decreased quadratically (P < 0.01) throughout the sampling period with few changes once grain reached 15.5% moisture. Differences observed in the digestibility of the blade/sheath were attributed to the effects of weathering. A third set of trials was conducted to evaluate the effects of by-product supplementation of calves grazing irrigated corn residue and supplemented with DGS or continuous access to lick tubs. The DGS treatment gained more (0.62 kg/calf daily) than the lick tub treatment (0.38 kg/calf daily; P < 0.01). Calves offered DGS consumed more supplement as a percentage of BW (0.52%) when compared with calves offered lick tubs (0.36%; P < 0.01) on a DM basis. Calves supplemented with DGS had a higher supplement efficiency (46.3% to 42.9%, DM basis) although no differences were present between treatments (P = 0.49). When analyzed on an OM basis, however, calves offered lick tubs had a numerically higher supplement efficiency (50.4%) in comparison to calves …

Response Of Grassland Songbirds To Grazing System Type And Range Condition, Stephen K. Davis, Brenda C. Dale, Tom Harrison, David C. Duncan

The Prairie Naturalist

Much of the remaining prairie in Canada is grazed by cattle and most grassland birds of conservation concern occupy such habitat. Identifying vegetation features related to grassland bird habitat selection that can be easily understood and measured by professional range managers and livestock producers on private lands is an important step towards conserving and restoring remaining grasslands. We conducted grassland bird surveys on 28 native mixed-grass prairie pastures in southern Saskatchewan to determine whether grazing system type (season-long vs. rotational) influenced avian abundance. Grazing system had no influence on abundance of grassland passerines. Conservation agencies that promote particular grazing systems …

Monitoring Standing Herbage Of Mid-Grass Prairie On The Fort Pierre National Grassland, South Dakota, Daniel W. Uresk

The Prairie Naturalist

Monitoring vegetation with a modified Robel pole on the Fort Pierre National Grassland was evaluated for combined shallow clay and loamy overflow ecological sites (dominated by warm-season grasses), and for clayey ecological sites (dominated by cool-season grasses). My objectives were to 1) develop a relationship between visual obstruction readings (VOR) and standing herbage, 2) provide guidelines for vegetation monitoring, and 3) evaluate vegetation monitoring during the growing season for clayey ecological sites. The relationship between visual obstruction readings and standing herbage was linear and regression coefficients were highly significant (P < 0.001) for both ecological types. Cluster analyses for shallow clay and loamy overflow ecological sites grouped the VOR and standing herbage (kg•ha-1) into 4 resource categories. Monitoring with 4 transects will provide adequate information to estimate standing herbage within 259 ha (1 section). Three resource categories (VOR + herbage) for clayey ecological sites were defined by cluster analyses. Monitoring with 4 transects was determined to provide reliable estimates of standing herbage. July validation of vegetation with the developed clayey ecological site model will provide reliable monitoring of standing herbage from July through November for this ecological site.

A Synoptic Review Of U.S. Rangelands A Technical Document Supporting The Forest Service 2010 Rpa Assessment, Matthew Clark Reeves, John E. Mitchell

USDA Forest Service / UNL Faculty Publications

The Renewable Resources Planning Act of 1974 requires the USDA Forest Service to conduct assessments of resource conditions. This report fulfills that need and focuses on quantifying extent, productivity, and health of U.S. rangelands. Since 1982, the area of U.S. rangelands has decreased at an average rate of 350,000 acres per year owed mostly to conversion to agricultural and residential land uses. Nationally, rangeland productivity has been steady over the last decade, but the Rocky Mountain Assessment Region appears to have moderately increased productivity since 2000. The forage situation is positive and, from a national perspective, U.S. rangelands can probably …

Effects Of Herbicides And Grazing On Floristic Quality Of Native Tallgrass Pastures In Eastern South Dakota And Southwestern Minnesota, Alexander J. Smart, Matthew J. Nelson, Peter J. Bauman, Gary E. Larson

Great Plains Research: A Journal of Natural and Social Sciences

Historic herbicide use and grazing have influenced natural diversity and quality of native pasturelands in the Great Plains. Floristic quality assessments are useful to assist agencies in prioritizing conservation practices to enhance native grasslands. The objective of this study was to determine the effects of past land-use practices on the floristic quality of remnant native pastures in eastern South Dakota and southwestern Minnesota. Floristic quality assessments were conducted on 30 native pastures and categorized by past management practices (herbicide application and grazing intensity). Mean coefficient of conservatism (C) and floristic quality index (FQI) were calculated for each site~Results showed that …

What Is The Potential Of Substituting Legumes For Synthetic Nitrogen In Warm Season Perennial Grasses Used For Stocker Cattle Grazing?, J. Biermacher, John A. Guretzky, Ryan Reuter, Maru Kering, Twain Butler, Job Springer, James Rogers, John Blanton, Joe Bouton

Department of Agronomy and Horticulture: Faculty Publications

Stocker cattle grazing warm season perennial grasses is an important economic activity in the southern Great Plains. Substantial increases in the price of nitrogen fertilizer is negatively affecting forage producers’ profitability. Two alternative nitrogen management systems that use annual and perennial legumes have been developed for bermudagrass pastures. The goal of the study is to determine if the legumes systems are more profitable than the conventional practice of applying synthetic sources of nitrogen. Enterprise budgeting techniques were employed to compare the economics of the legume systems relative to the common practice. Results of the two-year grazing study show that the …

In Situ Development Of Western Prairie Fringed Orchid Seeds, Protocorms, And Seedlings In Grazed And Non-Grazed Prairie Habitat, Bonnie Warner Alexander, Donald Kirby, Mario Biondini, Edward Dekeyser

The Prairie Naturalist

In 1989, the U.S. Fish and Wildlife Service listed the western prairie fringed orchid (Platanthera praeclara) as threatened. Although this orchid has been monitored for years, there is little scientific documentation of its biology, ecology, and phenology, nor the impacts of management activities on its populations. Our objectives were to document seed germination and seedling production rates after one year in situ, and compare seed germination in grazed and non-grazed prairie habitat in the Sheyenne National Grassland (SNG) in southeastern North Dakota. Of 18,717 planted seeds, we recovered 1,561 swollen embryos, 94 protocorms, and 51 seedlings. We documented no difference …

Alternative Methods For Wetland Restoration In The Rainwater Basin, Nebraska, Usa, Nancy Nicolai, James L. Stubbendieck

Department of Agronomy and Horticulture: Faculty Publications

South-central Nebraska is recognized as a focal point of the mid-continent migratory waterfowl flyway. Substantial wetland alterations led to a critical need for restoration. Managers have restored wetlands by scraping with heavy earthmoving equipment to remove excess organic material and near-monocultures of reed canarygrass (Phalaris arundinacea L.) but managers report high costs and topsoil perturbation. Moderate livestock grazing was tested to compare results with those achieved with mechanical techniques. Advantages of grazing could include low costs and less soil perturbation. During the 2006 and 2007 growing seasons, we compared cover of bare ground and open water and plant species …

Spatiotemporal Dynamics Of Black-Tailed Prairie Dog Colonies Affected By Plague, David J. Augustine, Marc R. Matchett, Theodore P. Toombs, Jack F. Cully, Tommy L. Johnson, J. G. Sidle

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Black-tailed prairie dogs (Cynomys ludovicianus) are a key component of the disturbance regime in semi-arid grasslands of central North America. Many studies have compared community and ecosystem characteristics on prairie dog colonies to grasslands without prairie dogs, but little is known about landscape-scale patterns of disturbance that prairie dog colony complexes may impose on grasslands over long time periods. We examined spatiotemporal dynamics in two prairie dog colony complexes in southeastern Colorado (Comanche) and northcentral Montana (Phillips County) that have been strongly influenced by plague, and compared them to a complex unaffected by plague in northwestern Nebraska (Oglala). …

Grazing Intensity Effects On Northern Plains Mixed-Grass Prairie, Wendi M. Rogers, Donald R. Kirby, Paul E. Nyren, Bob D. Patton, Edward S. Dekeyser

The Prairie Naturalist

We evaluated the effects of long-term (1988 to 2000) grazing on northern mixed-grass prairie at tI.e Central Grasslands Research Extension Center in south-central North Dakota. We did not detect a difference in herbaceous basal cover between grazing intensities following 12 consecutive years of season-long moderate (50% removal of annual above-ground standing crop) and heavy (80% removal of annual above-ground standing crop) grazing. However, both moderate and heavy grazing intensities reduced above-ground herbaceous standing crop, total root biomass, and soil organic carbon. Moderate grazing intensity maintained a greater amount of deep (10 to 20 cm) and total root biomass relative to …

Postweaning Performance Of Hair And Wool Sheep And Reciprocal-Crosses On Pasture And In Feedlot, M. A. Brown, H. S. Mayeux

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Lambs from three diallel-mating plans (Dorset-St. Croix, n=140; Rambouillet-Gulf Coast, n=80; Katahdin-Suffolk, n=78) and a terminal-cross mating plan (Suffolk rams mated to Dorset, St. Croix and reciprocal-cross ewes, n=100) were used to evaluate postweaning grazing performance of traditional meat breeds and tropically adapted breeds of sheep.

The Relations Of Vegetative Composition And Cattle Grazing On Nebraska Range Land, T. E. Brinegar, F. D. Keim

Historical Research Bulletins of the Nebraska Agricultural Experiment Station

The objectives of the studies reported in this paper were: (1) to obtain an analysis of the vegetation in tall and short grass range lands, (2) to observe the activities of cattle on the range, and (3) to determine the effects of grazing upon vegetation.

Nebraska Pastures: Seeding And Management, A. L. Frolik, E. F. Frolik

Nebraska Agricultural Experiment Station: Historical Circulars

Pastures are an important source of feed in the livestock industry. Approximately 70 per cent of the income from Nebraska farms is from the sale of livestock and livestock products, and for this reason consideration should be given to the maintenance of good pastures. Poor pastures, like other poor crops, are expensive. Good grass cover is also an effective means of conserving the soil resources.