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. The third year of a winter canola seeding date and rate study was planted in early and mid-August, 2010 at 4#/A and 8#/A. Winter canola planted on August 19, 2009 that was severely injured by cold weather in October and November yielded 1,355#/A and 820#/A for the 8#/A and 4#/A respectively. Spring canola was replanted in April 2010 in winter-killed winter canola plots that had been planted August 30, 2009. One week before harvest in 2010 a hail storm destroyed the spring canola crop. A herbicide study was initiated in the fall of 2010 to evaluate the efficacy of three grass herbicides for the management of cereal rye in winter canola. All harvested samples (2009 and 2010) were analyzed for oil content and quality. Obj. 1B. A new spring canola study was established in Okanogan, WA to evaluate three varieties planted in 7-inch row spacing (5#/A) and 14-inch row spacing (10#/A). The spring canola no-till planting method study was concluded in WA and OR. Five methods of planting were evaluated in OR and six methods in WA. In 2010, spring canola yields ranged from 750 to 1,115#/A in WA and 315 to 550#/A in OR. Oil quality and content were analyzed and % oil averaged 28% in WA and 33% in OR. Obj. 2A. A long-term study has been initiated at Ralston, WA to determine the feasibility of integrating alternative forage and biofuel crops into wheat-based production systems in the low- to intermediate-rainfall zones. Forage triticale was planted no-till and harvested (2010) and after a season of chemical fallow, winter canola will be planted (2011). Data collected include yield, biomass, and soil moisture. Objective 4B. Agroecological zones (AEZ’s) have traditionally been defined by integrating multiple layers of biophysical (e.g. climate, soil, terrain) and occasionally socioeconomic data to create unique zones with specific ranges of land use constraints and potentials. Our approach to defining AEZ’s assumes that current agricultural land uses have emerged as a consequence of biophysical and socioeconomic drivers. Therefore, we are exploring the concept that AEZ’s can be derived from classifying the geographic distribution of current agricultural systems (e.g. the wheat-fallow cropping system zone) based on spatially geo-referenced annual cropland use data that is currently available through the National Agricultural Statistical Service (NASS). The initial steps in developing a methodology for defining major AEZ’s and subzones based on a single year of NASS data look promising. Next steps include delineating and evaluating regional AEZ boundaries based on this approach.
1. No-till planting methods were identified for spring canola in the low- to intermediate-rainfall zones of the Pacific Northwest. Information on planting no-till spring canola is needed so growers can adopt conservation tillage practives to reduce erosion while introducing biofuel crops into a wheat-fallow production system. Planting methods tested over two years and at two locations included a double-disk opener, a double-disk opener with seed tubes removed for broadcasting seed, a double-disk opener for broadcasting seed followed by a roller, a Kile opener, and a cross-slot opener. For both locations, both years, ARS scientists in Pullman, WA found the highest yield was with the double-disk openers and the lowest yield was when the seed was broadcast. Adoption of conservation tillage spring canola planting practices by wheat growers would increase farm diversification, markets, sustainability, and environmental quality.
Young, F.L., Ball, D.A., Thill, D.C., Alldredge, J.R., Ogg Jr, A.G., Seefeldt, S.S. 2010. Integrated weed management systems identified for jointed goatgrass (Aegilops cylindrica) in the Pacific Northwest. Weed Technology. 24:430–439. DOI: 10.1614/WT-D-10-00046.1.