in order to study the effect of soil nitrogen content and water hardness on glyphosate efficacy on common lambsquarter (chenopodium album l.) and redroot pigweed (amaranthus retroflexus l.) control, an experiment was carried out as a completely randomized design in a factorial arrangement with three replications. experimental treatments were included soil nitrogen content (18, 50, 90, 200 and 3...

One hundred fifty Simmental-Hereford cows and calves were used in a 3-yr study to evaluate three creep grazing treatments and an early weaning treatment on cow and calf performance during midsummer (July to September). Calves were approximately 150 d of age and averaged 178.6 kg when treatments were initiated. Tifleaf pearl millet (Pennisetum Americanum L. Leeke) was used as the forage for two ...

Replicated cow herds of 15 Angus x Hereford (AH) and 15 Brahman x Hereford (BH) F1 cows each were placed on native rangeland (NR) or native rangeland-complementary forage (NRCF) systems. The NR was 8.1 ha of sagebrush-mixed prairie per cow-calf unit and the NRCF used the same mixed prairie complemented by .4 ha of double-cropped winter wheat and summer annual forage replacing about 30% of the m...

We reconstructed the historical trends in atmospheric deposition of nitrogen to Cape Cod, Massachusetts, from 1910 to 1995 by compiling data from literature sources, and adjusting the data for geographical and methodological di!erences. The reconstructed data suggest that NO 3 -N wet deposition to this region increased from a low of 0.9 kg N ha~1 yr~1 in 1925 to a high of approximately 4 kg N h...

Soil water, salinity and nitrogen content are three major factors affecting crop production in arid and semi-arid areas. This study was performed in two years of 2009 and 2010 in a semi-arid area in order to investigate the effects of irrigation water quantity (as main plot), quality (saline water, as sub-plot), nitrogen fertilizer (as sub-sub plot) and their interactions on growth and yiel...

the study was carried out to examine the effects of urban sewage and nitrogen fertilizer levels on yield quantity and quality forage of sweet corn was evaluated in yasouj at 2009. the main experimental factor consisted of 5 irrigation levels including: common irrigation water without sewage effluent until the end of plant growth (i1), the first half of plant growth period with sewage effluent a...

to study the effect of seed sowing rate, different levels of nitrogen and different sowing dates on canola cultivar hyola401, a field experiment was conducted during 2005-2006 at safiabad agricultural research center. the design was a split split plot in a completely randomized block basis of 3 replications. main plots consisted of 3 levels of sowing dates (6, 26 nov and 16 dec), sub plots of 3...

For a cropping system to be sustainable, should not only the soil nitrogen (N) content be preserved but also the N runoff be minimised. Finding a simple but robust way to estimate N runoff would thus be a great advantage when evaluating cropping systems. In this study all major N flows in six different cropping systems, each covering 0.18 ha of a separately pipe drained field lysimeter, located...

The objectives of the current study were to determine the amounts of aboveand below-ground plant biomass production, P uptake by forage, and P concentration of cool-season grass forage as influenced by management and season. Five forage management treatments were evaluated over 3 years in smooth bromegrass (Bromus inermis Leyss) pastures. Management practices were: ungrazed (U), hay harvest/fal...