1a. Objectives (from AD-416):
The goal of this research project is to identify cultural practices and technologies that improve economic viability and environmental sustainability of inland PNW dryland wheat production systems. The specific objectives are fourfold and include: Objective 1: Develop cropping practices for improving crop water use in dryland production systems and landscapes across PNW agroecological zones. (Pullman all of Obj 1) Sub-objective 1A: Optimize crop establishment practices and crop water use for improving the performance of winter canola. Sub-objective 1B: Improve stand establishment methods for spring canola to minimize weed competition and increase crop water use. Sub-objective 1C: Contrast fall-planted facultative wheat and spring-planted wheat for abilities to suppress weeds and increase yield, profitability, and crop water use. Sub-objective 1D: Determine effects of Russian thistle on crop water use, and production costs and quality of forage spring triticale. Objective 2: Evaluate cropping system diversification strategies (forage and biofuels) for increasing agronomic performance of agricultural landscapes across PNW agroecological zones. Sub-objective 2A: Determine productivity and profitability of integrating alternative forage and biofuel crops into wheat-based production systems. (Pullman) Sub-objective 2B: Determine production potential of perennial biofuel and forage crops incorporated as riparian buffers in agricultural landscapes. (Pendleton and Pullman) Objective 3: Assess how new optical light reflectance spectrometers (advanced technology) can be used to increase cropping system performance in agricultural landscapes. (Pendleton – all of Obj 3) Sub-objective 3A: Apply information from on-combine yield monitors and optical sensors into site-specific nitrogen (N) application thereby improving grain quality and yield, and N use efficiency of cereal crops. Sub-objective 3B: Assess the quantity and quality of wheat residue at site-specific field locations across farm fields. Sub-objective 3C: Measure and map determinants of grain quality value (i.e. test weight, protein concentration, and foreign weed material), and apply this information into grain segregation on a combine harvester. Objective 4: Synthesize available crop and cropping systems research across PNW agro-ecological zones to assess biophysical production factors influencing cropping system performance and ecosystem services. Sub-objective 4A: Compile and summarize existing databases of dryland crops and cropping systems to calibrate and corroborate process-oriented models. (Pendleton) Sub-objective 4B: Utilize existing datasets and process-oriented models to spatially evaluate the suitability of past, present, and future cropping system strategies. (Pullman) NP216 Cross-location project associated with Pendleton, OR 5356-13210-003-00D (Long).
1b. Approach (from AD-416):
1A&B. Several multi-year field studies will be conducted in numerous locations in the low to intermediate rainfall zones to evaluate seeding date, rate, and methodologies for winter and spring canola in order to improve crop establishment. Data collected include seed-zone water, soil profile water storage, weed populations, crop yield, and oil and meal content. 1C. A multi-year study will be conducted in the high-rainfall zone to compare grain yield and wild oat suppressive ability of facultative wheat planted in late fall with that planted in April/May the following spring. Within each time of planting, wheat will be grown non-treated or treated with recommended or half the recommended rate of a wild oat herbicide. Wild oat population and seed production will be measured prior to grain harvest and crop yield and quality (dockage) will be determined. Consumptive water use will be determined with gravimetric soil profile samples before planting and after harvest. 1D. Spring forage triticale will be planted in a naturally infested field of Russian thistle in a 2 to 3-year study. Half the plots will be sprayed with a herbicide to control Russian thistle and the weed will be allowed to grow in the remaining plots. Forage quality of the triticale will be analyzed with and without the weed and the total weed and crop biomass will be weighed. Total systems production costs will be determined and crop water use will be calculated. 2A&B. Field experiments will be conducted to evaluate the performance of diversified cropping systems in the low, intermediate, and high rainfall zones. A 3-yr rotation of winter wheat, spring canola, and forage winter triticale will be compared to a rotation of winter wheat, spring barley and spring pea in the high rainfall zone while a 3-yr rotation of winter triticale, spring canola, and fallow will be compared to a rotation of winter wheat, spring barley, and fallow in the intermediate rainfall zone. The bioenergy and forage potential of two perennial species grown along stream channels will be evaluated within all rainfall zones. Biomass, grain yield, and economic and risk analyses will provide insight into overall performance. 4B. Specific themes will be defined that can be flexibly used to derive Agroecological Zones (AEZ) based on criteria that are relevant to the question asked. Three basic steps to design and develop relevant AEZ will be used: 1) Generate raster surfaces of biophysical and socio-economic variables through spatial interpolation of data; 2) Generate a spatial framework of AEZ by combining basic raster themes into more integrated variables; and 3) Characterize spatial units in terms of relevant themes such as zones separating commonly practiced cropping systems. After AEZ development, model calibration, and long-term field studies synthesis, what-if scenarios will be developed and current and future cropping systems will be evaluated. In collaboration with scientists directly involved with specific modeling we will apply calibrated models to long-term data sets to corroborate these models under a wide-range of regional conditions. Replacing 5348-22610-002-00D 09/11/08.
3. Progress Report:
Obj. 1A. Data from the 5-yr winter canola seeding date and rate study as well as the shovel vs. no shovel study has been analyzed. The major discovery was that the optimum time of planting winter canola in the low- to intermediate-rainfall zone is based on rainfall and cool weather and not calendar date. Obj. 1B. A repeat of the first year’s spring canola variety by row spacing experiment was planted in three locations in the low-rainfall region of north central WA in 2012. In 2011 when averaged over row spacing, “Invigor” (glufosinate tolerant) spring canola yielded 935 lbs/acre (A) compared to the glyphosate tolerant, late maturing variety at 1,120 lbs/A and the early maturing variety at 1,045 lbs/A. Yields were slightly higher in the 7-inch row spacing for both the “Invigor” and the late maturing variety compared to the 14-inch spacing. Obj. 2A. A long-term cropping system study was initiated in 2010 to increase residue and soil moisture so that chemical fallow can replace traditional tillage summer fallow and winter canola can be planted no-till at an optimum time. In the fall of 2011 a tall winter wheat and winter triticale were planted no-till and will be harvested this summer with either a stripper header or conventional combine header. If soil moisture is within 2" of the soil surface in the current chemical fallow, winter canola will be planted no-till. Obj. 4B2. A spatial framework of Agroecological Zone (AEZ) was developed for the Inland Pacific Northwest by combining biophysical characteristics (climate, soil, terrain) with geo-referenced cropland use data available through NASS. This delineation of AEZs using biophysical and socio-economic variables will enable forecasting shifts in AEZs based upon climate change.
Walters, C.G., Young, F.L., Young, D.L. 2012. Economics of alternative management practices for jointed goatgrass in winter wheat in the Pacific Northwest. Crop Management. Online. DOI: 10.1094/CM-2012-0227-01-RV.