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. First year’s winter canola research was established at two locations in the wheat/fallow region. Winter canola was planted at two rates in mid-August and three rates in late August. Severe cold weather killed more than 50% and 100% of the plants in the mid-August and late August plantings respectively. Spring canola was seeded in 2010 in the winter-killed, late-planted areas. In a second study, winter canola was planted with shovels to move the hot, dry soil away from the seed and without shovels. Obj. 1B. The second year’s experiments with spring canola were established at sites near Ralston, WA and Echo, OR. Five methods of planting spring canola were evaluated in terms of grain yield and included broadcasting seed with and without incorporation, planting seed with a double disk drill, and planting seed with cross slot and hoe-type, no-till drills. A sixth method was evaluated at Ralston and consisted of a second type of hoe opener. Spring canola yields varied with planting method. In 2009, which was the first year of the study, yields ranged from 600 to 1100 lb/A at Ralston and 900 to 1400 lb/A at Echo. Obj. 4A. The Root Zone Water Quality Model (RZWQM) was set up and pre-calibrated for simulation of winter wheat and spring wheat cropping systems in the lower rainfall areas of the inland Pacific Northwest. Data, including grain yield, soil water, soil and crop nutrients, were used from long-term field trials at Pendleton, OR and Ralston, WA. Field-measured values of soil profile water content, crop residue mass, soil profile nitrate, bulk density, and soil organic matter content were used as initial conditions for model simulations. Obj. 4B2. Rasters of biophysical data to recreate agroclimatic zones of Douglas et al., (1990) were completed and agroclimatic zones mapped for the PNW. Projections of climate change for 2030 and 2050 were integrated into these data and shifts in agroclimatic zones were mapped.
1. Integrated weed management systems identified for jointed goatgrass in the Pacific Northwest. Information on integrated weed management (IWM) systems is needed so growers can adopt effective long-term jointed goatgrass strategies to reduce the negative impact of this invasive weed in 5 million acres of winter wheat in the PNW. ARS Scientists in Pullman, WA, conducted a six-year, three-state, study to evaluate and identify effective IWM systems for jointed goatgrass management. A combination of a one-time stubble burn, three years out of winter wheat and the integrated practice of planting winter wheat had the highest grain yield and quality and lowest weed densities. Adoption of the IWM system by wheat growers would reduce jointed goatgrass competition and infestations, decrease farm chemical inputs, and improve farm profitability, sustainability, and environmental quality.
5. Significant Activities that Support Special Target Populations
Organized, co-hosted with the Colville Confederated Tribes, and provided materials for a Canola Recognition Day held at Paschal Sherman Indian School. Attendees included Colville Confederated Tribe Council, School Board, and Committee members; USDA-ARS and WSU scientists; local growers; and county extension personnel. Highlight of the event was filling a Paschal Sherman Indian school bus with biodiesel that was produced by local growers based on ARS research, crushed by the Colville Confederated Tribes, and processed by WSU extension. Organized a Canola Partnership in north central WA including Colville Confederated Tribes, USDA-ARS, WSU Extension, local schools and growers, and WA State Dept. of Ag. to develop alternative crops for providing food, fuel, and jobs for the region.
Al-Mulla, Y.A., Wu, J.Q., Singh, P., Flury, M., Schillinger, W.F., Huggins, D.R., Stockle, C.O. 2009. Soil Water and Temperature in Chemical versus Reduced-Tillage Fallow in a Mediterranean Climate. Applied Engineering in Agriculture. Vol. 25(1): 45-54.