Urea is frequently surface applied to winter wheat (Triticum aestivum L.) during cold weather months (October–April) in the semiarid northern Great Plains. This study was conducted quantify NH3 volatilization loss from surface-applied urea (100 kg N ha−1) and amended with N-(n-butyl) thiophosphoric triamide (NBPT) this period. Ammonia emissions were quantified by a micrometeorological integrated horizontal flux method samplers placed on mast center of circular plots (20-m radius). Cumulative...

Reduction of arsenate [As(V)] to arsenite[As(III)] influences the mobility and toxicity arsenic (As), yet mechanisms controlling rate reduction in soils natural waters are poorly understood. The goal this study was determine processes affecting rates both aqueous sorbed phase As(V). experiments were conducted anaerobically serum bottles with a range glucose As(V) concentrations. Serum inoculated microorganisms extracted directly from an agricultural soil having naturally elevated...

Miller, P. R., Lighthiser, E. J., Jones, C. A., Holmes, J. Rick, T. L. and Wraith, M. 2011. Pea green manure management affects organic winter wheat yield quality in semiarid Montana. Can. Plant Sci. 91: 497–508. Organic farmers Montana desire manures that supply sufficient soil nitrate-N (NO3-N) to subsequent crops with minimal water depletion. Spring pea (Pisum sativum L.) were compared at the bloom pod stages for NO3-N contribution use, (Triticum aestivum grain a long-term farm northern...

Pea ( Pisum sativum L.) is increasingly being rotated with wheat Triticum aestivum in Montana. Our objective was to compare economic net returns among wheat‐only and pea–wheat systems during an established 4‐yr crop rotation. The experimental design included three (tilled fallow–wheat, no‐till continuous wheat) (pea–wheat, pea brown manure–wheat, forage–wheat) as main plots, high low available N rates subplots. Net were calculated the difference between market revenues operation input costs...

Annual legume green manure (LGM) cover crops may have potential in dryland wheat ( Triticum aestivum L.) production areas where rotation with whole‐year summer fallow is practiced. No‐till cropland management enhances soil water conservation, possibly enabling cropping, but tillage be necessary to stimulate mineralization of LGM N time affect crop yield. A 2‐yr LGM‐wheat sequence study was repeated three times Montana, mean annual precipitation 356 mm. Spring‐planted pea Pisum sativum and...

The vast majority (82 %) of the earth's cultivated area is not irrigated, and half in semi-arid regions where water tends to limit crop growth. In dryland agroecosystems, any precipitation transpired indicates yield that below potential. Precipitation partitioned deep percolation can transport nitrate out root zone, reducing nitrogen use efficiency potentially contaminating groundwater. To mitigate loss drought, practice chemical summer-fallow (suppressing plant growth for a full growing...

Abstract The practice of liming to remediate contaminated soils and mine tailings has the potential mobilize arsenic (As), due pH dependence As sorption reactions on oxide minerals layer silicates. objectives this study were determine effects mobility in identify possible mechanisms controlling mobilization with increased pH. Six tailing samples obtained from an abandoned copper smelter near Anaconda, Montana analyzed for total soluble constituents using saturated paste extractions....

In the North American northern Great Plains (NGP), legumes are promising summer fallow replacement/cropping intensification options that may decrease dependence on nitrogen (N) fertilizer in small grain systems and mitigate effects of soil organic matter (SOM) losses from fallow. Benefits not be realized immediately semiarid conditions though, longer-term intensified cropping this region unclear, particularly no-till systems. We compared four wheat (Triticum aestivum L.) systems–summer...

Abstract Despite a plethora of studies on the effects cover crops soil health, few published papers have reported plant functional group and richness especially in semiarid regions. We initiated no‐till study Montana 2012 that consisted Pea ( Pisum sativum L.), four two‐spp single groups (Brassica, Fibrous‐rooted, Legumes, Tap‐rooted), three‐functional mixes, four‐functional mix (Full), summer fallow control (Fallow). Cover were terminated with herbicide when pea was at first flower stage,...

Replacing summer fallow practices with annual legumes as green manures (LGMs) may increase the sustainability of northern Great Plains wheat (<i>Triticum aestivum</i> L.) systems. Viability hinges on soil water use management and realizing biologically fixed nitrogen (N) benefits. Plot-scale research has shown that managing LGMs first-flower stage termination no-till conserves rotational N benefits can grain quality. Nonetheless, farmer adoption been negligible. To better understand this...

Energy consumption, intensity, and productivity are indicators of agricultural sustainability in the face fossil energy scarcity price volatility. In this study, budgets embodied crop production inputs were compiled for 14 paired pulse (annual grain legume)-wheat wheat-wheat sequences using data collected from Montana farmers. We report two performance metrics: net yield (NEY), content harvested minus required to produce it, intensity (EI), ratio input mass harvested. Nitrogen fertilizer...

ABSTRACT Drought conditions are common in the northern Great Plains of United States, affecting crop yield and quality. Phosphorus (P) fertilizer applications have been found to increase drought tolerance, although there is a lack published work this area. The goal study was determine effects P fertilization on tolerance malt barley (Hordeum vulgare). Here, 60 cm tall PVC columns were filled with either silt loam that had medium soil test phosphorus (STP) level or same diluted 1:1 (v/v)...

Transition to no‐till (NT) and organic (ORG) farming systems may enhance sustainability. Our objectives were compare transitional crop productivity soil nutrient status among diversified NT ORG cropping in Montana. Three designed as 4‐yr rotations, including a pulse (lentil [ Lens culinaris Medik.] or pea Pisum sativum L.]), an oilseed (canola Brassica napus L.] sunflower Helianthus annuus L.]) two cereal crops (corn Zea mays L.], proso millet Panicum miliaceum wheat Triticum aestivum L.])....

Abstract A greenhouse study was conducted to determine the effects of low‐rate commercial humic acid (HA) on phosphorus (P), iron (Fe), and zinc (Zn) availability spring wheat yields, in both a calcareous soil noncalcareous soil. In Phase I, soluble P concentrations were monitored at 1.9, 3.8, 5.7 cm from monoammonium phosphate (MAP) fertilizer band that had either been coated with one two HA products equivalent 1.7 kg ha−1, label rate, or left uncoated. Sampling occurred periodically up 48...

Abstract Nitrogen loss from cultivated soils threatens the economic and environmental sustainability of agriculture. Nitrate (NO 3 − ) derived nitrification nitrogen fertilizer ammonified soil organic may be lost via denitrification, producing dinitrogen gas (N 2 or greenhouse nitrous oxide O). that accumulates in is also subject to leaching loss, which can degrade water quality make NO available for downstream denitrification. Here we use patterns isotopic composition observed 2012 2017...