Project Number: 5356-13210-002-00
Project Type: Appropriated

Start Date: Nov 21, 2006
End Date: Nov 30, 2008

Objective:
1. Compare crop yield and economic returns from a four-year crop rotation (wheat-fallow-wheat-legume) under conventional, inversion tillage and no-tillage. 2. Determine feasibility of winter wheat following winter or spring grazing of livestock (sheep or cattle) for animal performance, wheat productivity, weed control, and soil conservation. 3. Develop alternative harvesting technology that harvests the crop and sorts the grain by density, sizes crop residue for optimum no-till drill performance under heavy residue conditions, and collects harvested residue for production of biofuels. 4. Determine guidelines for biomass removal for energy production and its impacts on important soil properties and processes across inland PNW precipitation zones.

Approach:
Four-year experiments will compare crop yield and economic returns of a four-year rotation of winter wheat-summer fallow-winter wheat-broadleaf crop (e.g. chickpea or mustard) under no-till vs. conventional inversion tillage. In addition, a three-year study will be conducted to determine economic returns from integrating dryland wheat with winter-spring grazing of livestock. Standard enterprise budgets will be conducted to assess net returns from tillage system or grazing. For tillage, economic analyses will be based on the actual sequence of operations that occurred in each tillage system. Gross value will be based on current and average market quotes for a specific crop input. Other costs will include market return for farmer¿s land, machinery, and labor. Government payments will be included in the analysis. In addition, specialized engineering procedures will be used to develop new, innovative techniques for harvesting that add value by segregating grain by quality. We will also develop and evaluate a mechanical system that harvests wheat, prepares crop residue for optimum non-till drill performance under heavy residue conditions, and collects harvested residue for producing biofuels. Field studies will be conducted to determine the transitional effect of a shift to biomass production from crop residues and biomass energy crop production. Treatments consist of crop, biomass removal, and net primary productivity level. Crops include winter wheat, canola, monoculture of switchgrass, and a polyculture mix of switchgrass, cool season grasses, and legumes. Crop residues from wheat and canola will be removed at commercially achievable rates. Each crop will be managed under three irrigation regimes intended to create three productivity levels representative of low, intermediate, and high production regimes. Irrigation application amounts will be varied as a fraction of evapotranspiration (ET) rate ¿ 50, 75, and 100%. Experimental design is a split-split plot with four replications with cropping system (corn, wheat, switchgrass) as the main factor, productivity level (low, intermediate, high) as the first split, and residue removal as the final split.