eaten it? Does it grow faster or differently from un-grazed algae? To address these questions, an experiment conducted in streamside channels documented the re-growth of algae following grazing by two mayfly species. We found that algal re-growth did not depend on which mayfly species ate it; rather, it was the duration of grazing that mattered. The longer algae was grazed, the faster it grew. ...

Cattle and sheep grazed together and separately from April to October during 3 yr. Initial forage composition was 29% Kentucky bluegrass (Poa pratensis L.), 11% white clover (Trifolium repens L.), and 60% weeds. There were six Angus cow-calf pairs or six ewes (1/2 Dorset x 1/4 Finn x 1/4 Rambouillet) with 11 lambs per each of three pasture replications for single animal species. Six cow-calf pa...

Integrating use of seeded perennial cool-season grass pastures with native rangeland can increase available forage and provide a high plane of nutrition for grazing livestock. Our objective was to compare performance of yearling beef heifers grazing native rangeland with those grazing an integrated system that included seeded forages. Twice-replicated, 3-ha pastures seeded to either ‘Rosana’ we...

Intraspecific variation in the strength of inducible plant defenses plays a central role in the interactions between plants and herbivores. Studies of this variation are typically conducted in the greenhouse or laboratory rather than the field. We simultaneously manipulated densities of local consumers in the field within Maine and South Carolina populations of the smooth cordgrass Spartina alt...

rangeland shrubs may provide mechanical facilitation on their understory plants, by protecting themagainst the livestock grazing. however, such a facilitation effect may vary depending on the rangelandutilization rate. in a field research, mechanical facilitation of rangeland shrubs was compared in ahighly grazed, a moderately grazed and an enclosure site; in an arid rangeland, kakhak, gonabad,...

Although feed intake and efficiency differences in growing cattle of low and high residual feed intake (RFI) classification have been established, little is known about the difference in grazed forage intake between beef cows of known RFI classification. Two experiments were conducted using Hereford cows for which RFI had been determined as heifers using the GrowSafe 4000E feed intake system, a...

This chapter considers the emissions of ammonia (NH3), nitrous oxide (N2O), other oxides of nitrogen (NOx), carbon dioxide (CO2), methane (CH4), and non-methane volatile organic compounds (NMVOCs) from agricultural soils to which nitrogen (N)-containing fertilizers are applied. For NH3, emissions following application of animal manures to land are considered in SNAP code 100900, Manure Manageme...

Rangelands are globally extensive, provide fundamental ecosystem services, and are tightly coupled human-ecological systems. Rangeland sustainability depends largely on the implementation and utilization of various grazing and burning practices optimized to protect against soil erosion and transport. In many cases, however, land management practices lead to increased soil erosion and sediment f...

Livestock grazing in the shortgrass steppe of the Intermountain region of British Columbia is predicted to have significant effects on grassland habitats and their associated ground-nesting bird communities. We tested whether grazed and ungrazed sites could be discriminated on the basis of their vegetation communities, whether the abundance of two ground-nesting bird species, Vesper Sparrow (Po...