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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
151

Irrigation and nitrogen treatment of forage crops in various mixtures and systems of management /

Prine, G. M. January 1957 (has links)
No description available.
152

Poultry Litter as a Nutrient Source for Low Input Forage Systems

McGrath, Steven Russell 04 June 2009 (has links)
Despite high volumes of manure production in the Shenandoah Valley, there are still areas of forage production in the Shenandoah Valley that are nutrient deficient, because manures have traditionally been applied to higher value row crops. Furthermore, anecdotal reports have suggested that application of poultry litter to pastureland may increase the abundance of weeds. This study was conducted to compare the effects of poultry litter and inorganic fertilizers on soil fertility, aboveground botanical composition and soil seed bank composition of established mixed naturalized pastures. Two sites each had the following treatments applied for two consecutive years: 1) split application of litter: 3.36 Mg ha-1 in spring and 3.36 Mg ha-1 in summer; 2) inorganic fertilizer at same N, P and K rates as Trt. No. 1; 3) single application of litter: 6.72 Mg ha-1 in spring; 4) inorganic fertilizer at same N, P and K rates as Trt. No. 3; 5) unfertilized control. Forage yield, soil pH, Mehlich 1 P (M1P), P balance, water soluble phosphorus (WSP), shifts in aboveground botanical composition, seed bank composition, and species richness (SPR) were monitored during this experiment. In addition, we examined whether poultry litter carries germinable weed seeds that can be transferred to forage systems after application. On average, soil pH was 0.2 higher for litter than chemical fertilizer treatments, but this difference was not significant. Mehlich 1 P and WSP both increased throughout the two years, but no significant differences were found amongst split and single application or litter and inorganic fertilizers. Phosphorus balance analysis indicated that forage yield did not remove adequate P to prevent environmental concerns, when using N based applications. Fertilization increased yield 3.5 Mg ha-1 on average and yield responses to application timing and fertilizer types were similar. Desirable species abundance increased significantly (linear regression, P< 0.05) over time in both fertilizer and poultry litter application treatments. Furthermore at one site, Shenandoah County, poultry litter application actually reduced the number of weedy species in plots (P=0.04). Weedy plant abundance did not differ at either site, and no significant change in species richness (number of species/area) was observed at Rockbridge County for any treatment. No treatment effects were found for seed bank species richness and number of germinated seeds (m-2). No seedlings germinated directly from poultry litter collected from several sites in Virginia. Poultry litter was comparable to inorganic fertilizer in terms of increasing soil WSP, M1P, forage yield, and above ground composition of desirable forage species. Timing of application made no difference. Additionally, our results indicate that poultry litter has no viable seed and does not increase weed abundance in mixed naturalized pastures. / Master of Science
153

Small Grains Forage Management and Evaluation in Central Texas

Franks, Aaron Michael 03 October 2013 (has links)
Hard Red Winter (HRW) and Soft Red Winter (HRW) wheat classes (Triticum aestivum L.) and oat (Avena sativa L.) are commonly established as a source of winter and spring forage for cattle grazing in many regions of Texas and the U.S. Southern Great Plains. Small grains used in these grazed systems offer the flexibility of management for season long forage production or production of both forage and grain (dual-purpose). Many commercially available and experimental cultivars are continually evaluated on their ability to produce grain, but little yield data is available on wheat and oats under dual-purpose management systems. In forage production systems, soil fertility management is also an integral component in meeting specific yield goals that producers depend upon to sustain adequate animal performance. Current nitrogen (N) recommendations in Texas are based on heavy, moderate, and light levels of grazing. To address these issues, two-year studies were initiated at three locations in Central Texas. The objectives of these studies were; (1) to evaluate thirty wheat and ten oat cultivars based on forage production and grain yield to identify those best suited to dual-purpose management; (2) to determine winter wheat forage yield potential at varying levels of N fertility; and (3) to evaluate five minimally invasive and non-destructive methods of quantifying forage yield. Results from dual-purpose cultivar evaluations included significant differences in forage yield, nutritive value, and grain yield between cultivars and species. Overall, oat produced less forage than either class of wheat, but Mg content was generally higher in oat. For grain production, SRW performed better under irrigation, but in dryland situations both wheat classes performed equally. We also found that pre-plant N fertilizer significantly reduced stand establishment in dry environments. The 67 kg ha-1 pre-plant N and the 45 kg ha-1 top-dress rates produced the highest forage yield. Nutritive value generally increased as N application rate increased, even when no yield increase was observed. Hand clipping and canopy height both correlated very well with full plot harvest and visual ratings and NDVI had moderate relationships with full plot harvest. The relationship between ground cover and dry matter yield was variable and only weakly correlated.
154

Forage Herbage Accumulation and Nutritive Value Dynamics of a Mixed Cool-Season Grass Sward across Seasons

La Guardia Nave, Renata 27 June 2012 (has links)
No description available.
155

Hybridization in Panicum virgatum L.

Reeves, Dale Leslie. January 1962 (has links)
LD2668 .T4 1962 R44
156

Trends in the chemical composition and yield of Atlas forage sorghum as affected by stage of maturity, plant population, and row width

Long, Raymond Carl. January 1962 (has links)
LD2668 .T4 1962 L66
157

Composition of Arizona Forages, with Comparative Data

Catlin, C. N. 01 December 1925 (has links)
This item was digitized as part of the Million Books Project led by Carnegie Mellon University and supported by grants from the National Science Foundation (NSF). Cornell University coordinated the participation of land-grant and agricultural libraries in providing historical agricultural information for the digitization project; the University of Arizona Libraries, the College of Agriculture and Life Sciences, and the Office of Arid Lands Studies collaborated in the selection and provision of material for the digitization project.
158

Estimating Range Use with Grazed-Class Photo Guides

Schmutz, Ervin M. January 1978 (has links)
Revised publication
159

Use of Forage Crops for Livestock Production in Arizona

Dennis, Robert E., Lane, Albert M. 09 1900 (has links)
No description available.
160

Irrigated Perennial Pasture Test

Isaacson, Leonard, Dennis, Robert E., Parsons, David 09 1900 (has links)
No description available.

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