Performing Department
Crop and Soil Sciences
Non Technical Summary
In this project, we will optimize and demonstrate a direct-seeding (no-till) organic cropping system for the Palouse dryland farm. Our goals are to conduct research necessary to optimize the system and document economics, demonstrate the system and conduct outreach, and change producer outlooks on the feasibility of sustainable organic production in this region. The system depends on co-utilization of three recently developed / improved tools. These are a) new highly effective organic registered herbicides; b) sensor-guided selective herbicide application, the WEED-IT; and c) new locally adapted food grade (higher market value) winter pea varieties. These tools are essential and synergistic to provide the needed weed and soil management in a direct seed (no-till) system at an affordable cost. Our objectives are:Determine effectiveness and economics of capric/caprylic acid herbicide, winter peas, and WEED-IT technology as organic weed management tools.Determine interactions of organic herbicides, in field crop systems with and without winter peas, on soil health and insect populations.Determine sensitivity of major regional field crops and weeds to these herbicides.Provide extension and outreach to demonstrate effectiveness and increase interest in a locally adapted organic direct seed cropping system.The project uses a combination of field research, greenhouse research, field demonstrations, and varied outreach and discussion to accomplish the objectives.This project addresses three NOSB research priorities: 1) organic no-till systems, 2) side-by-side trials of organic materials and cultural methods, and 3) production and yield barriers to transitioning to organic production.
Animal Health Component
70%
Research Effort Categories
Basic
10%
Applied
70%
Developmental
20%
Goals / Objectives
We will:Conduct research necessary to optimize an organic cropping system using winter peas, organic herbicides, sensor-assisted spot spraying, and direct seeding for the Palouse dryland farm.Demonstrate and conduct outreach on options and effectiveness of the system and its components (winter peas, organic herbicides, sensor-assisted spot spraying).Document economics of the system and its components.Change producer outlooks on the feasibility of sustainable organic production in this region.
Project Methods
Determine effectiveness and economics of capric/caprylic acid herbicide, winter peas, and WEED-IT technology as organic weed management tools. Field plots will be managed at two certified organic farms, one in Washington and one in Idaho. These plots were planted in winter pea varieties in September 2019 to compare the varieties with differing weed management methods. A second set of plots will be established next to these in 2020. Economic returns will be determined. Data to be collected include:Amounts and costs of herbicides, seeds, equipment, fuel, and/or labor usedBiomass, yield, moisture, test weight, protein of peas and following croppea and weed %N, and d15N to estimate biologically fixed Ncrop and weed cover, and weed biomass and species at harvestEffects on the following crop including weed pressure and soil health effects will be tracked.2. Determine interactions of organic herbicides, in field crop systems with and without winter peas, on soil health and insect populations.This objective is to study important "secondary" effects of the main treatments. Insect populations and soil health are significant contributors and indicators of system health. Pea "weevil" Bruchus pisorum is a grave concern and may vary among pea varieties. In addition, the active chemicals in the organic herbicides of this study may affect Bruchus or other insects.count and identify weevils and predator insects at 50% flowering of peas. Also quantify % weevil infection in harvested peas.annual soil health by 30 cm to 120 cm including: bulk density, pH, available macronutrients, mineralizable N, dehydrogenase activity, total and active C, water holding capacity. In addition: soil pH at 0-5 and 5-10 cm to test organic acid herbicide effect on field soil pH.3. Determine sensitivity of major regional field crops and weeds to capric/caprylic and d-limonene herbicides.This objective is required because of the new application of capric + caprylic acid in field crops. The relative sensitivity of primary weeds and field crops will determine their best uses, hazards, and crop-specific expenses. And, although this material is composed of fatty acids that biodegrade, its effective herbicidal life on the soil surface is not well understood. In particular in our dry surface soils in late summer to early fall (when winter crops are sown), biological decomposition can be very slow. There is producer concern that residual organic herbicide may burn emerging seedlings. A replicated greenhouse and lab study will test the residual effects and breakdown rate of the organic herbicide, so that producers can be assured of a safe replant time after the final herbicide application. Tests will include:Collect soil from different sites, representing different soil organic C levels and pHApply herbicides at a range of dilutions on bare soil and soil with cereal residue cover, at moisture from 5% to 25%.Test different timing of herbicide application vs. seed planting (including applications of herbicide after seeding but before emergence) for plant-back sensitivity of wheat, barley, hemp, canola, peas, lentils, and chickpeas to capric/caprylic acid and limonene herbicides.Apply herbicides at a range of dilutions to growing plants to test sensitivity of multiple varieties of wheat, barley, hemp, canola, peas, lentils, and chickpeas; as well as common weeds at different life stages and height/size to determine effective concentrations to use in field depending on weed population.Additional test with thistles, which often become too tall to spray: cut plant at soil level, then spray base to test effectiveness of a mow + spray weed management technique vs. only cutting vs. only spraying.Spray both weed species and crop species at the soil level to test durability to girdling by herbicides and their compatibility with herbicide use between rows.4. Provide extension and outreach to demonstrate effectiveness and increase interest in a locally adapted organic direct seed cropping system, including organic herbicides and winter peas for managing weeds.Outreach of project will includeAnnual field days at multiple sitesPresentations and webinars to grower associationsarticles in grower magazinesExtension bulletinevaluations of grower responseMilestones:Prior to funding, 2019-2020:Establish plot areas at 2 certified organic farms Manage and monitor weeds Monitor pea weevil and predatorsYear 1, 2020-2021: Greenhouse sensitivity studies Manage and monitor weeds Monitor pea weevil and predatorsHarvest plots, analyze crop yield, quality Take soil samples and conduct analyses Field day presentations, demonstrations Year 2, 2021-2022:Greenhouse sensitivity studies Manage and monitor weeds Monitor pea weevil and predatorsHarvest plots, analyze crop yield, quality Take soil samples and conduct analyses Write manuscriptField day presentations, demonstrations Grower organization presentations and/or webinars Year 3, 2022-2023:Field day presentations, demonstrations Harvest plots, analyze crop yield, quality Take soil samples and conduct analyses Submit manuscript Grower organization presentations and/or webinarsGrower magazine submissionPrepare Extension article