Location: Soil Management Research2012 Annual Report
1a. Objectives (from AD-416):
Objective 1: Identify and develop new and alternative crops and cropping strategies for the northern U.S. • Sub-objective 1-1. Identify best adapted species/genotypes of new, alternative, and traditional crops for biofuels and bioproducts production in northern climates. • Sub-objective 1-2. Develop innovative, and improve existing strategies for managing new, alternative, and traditional crops. • Sub-objective 1-3. Determine environmental limitations on growth, development, and seed oil and nutritional quality of new, alternative, and traditional crops. Objective 2: Develop new strategies and decision aids to improve and increase the efficiency of weed management. • Sub-objective 2-1. Develop biological models of important invasive and prominent weeds, stressing critical life history events. • Sub-objective 2-2. Develop and improve weed management models. • Sub-objective 2-3. Explore feasibilities of entirely new strategies of managing weeds, focusing on increasing research on biologically-based integrated weed management.
1b. Approach (from AD-416):
Two mutually supporting approaches will be taken to meet our objectives. The first involves a series of field studies to identify new (e.g. cuphea, pennycress, and bifora) and alternative crop genotypes (e.g. camelina and calendula), develop practices to manage them, and use these crops along with traditional crops to develop alternative strategies (double- and relay-cropping) to add innovative economic and environmental benefits. Additionally, controlled-environment and field experiments will be conducted to determine environmental limitations (e.g. water and soil and air temperature) to growth of new and alternative crops. The second approach involves the integration of field and controlled-environment experiments of weed growth and development, innovative weed control methods, and computer modeling to develop decision support aids to efficiently and effectively manage weeds in cropping systems that include new and alternative, as well as traditional crops. Together the outcomes of this research will provide clientele with new knowledge, crops, and management tools to increase cropping efficiency and diversity in northern climates.
3. Progress Report:
We work on two primary objectives: 1) identify new and alternative crops and develop cropping strategies to integrate them with traditional crops to add environmental and economic benefits; and 2) integrate weed growth and development data, innovative weed control methods, and computer modeling to develop decision support aids to efficiently and effectively manage weeds in cropping systems for both new and traditional crops. Progress towards our first objective includes demonstrating that double-cropping soybean with winter camelina can be as or more economically profitable to farmers than growing a single full-season crop of soybean. Also, using camelina as a winter crop provides environmental benefits (e.g., prevention of soil erosion in the fall and early spring) that a single conventional full-season crop does not. Research also identified optimum nitrogen fertility, planting depth and seeding rate requirements for the new oilseed crops: camelina and calendula. Through a grant from the National Institute of Food and Agriculture (NIFA), our team joined forces with a large consortium of ARS and university scientists to begin studying alternative oilseed crops including camelina, canola, and oilseed mustard across the U.S. to determine which specie(s) and varieties are best suited for biofuel feedstock production for a given region. Aveda Corp. (owned by Estée Lauder) continues to support our research on cuphea and this work has led to improved methods for large-scale cuphea harvest. We are also working with Aveda to conduct a life cycle analysis of cuphea. Progress for our second research objective includes successful identification of pre- and post-emergence herbicides tolerated by calendula, camelina, and echium. These herbicides are being field tested to verify tolerances of camelina and echium. Results will be used for recommendations for their production. Our team also continued to research new organic weed control tactics. One method uses the grit of plant residues such as corn cobs propelled by compressed air to abrade and kill weed seedlings within the same row that the crop is growing. A prototype multi-row, tractor-pulled applicator was constructed by collaborating agricultural engineers at South Dakota State University through a North Central-Sustainable Agriculture Research & Education (NC-SARE) grant to our team and is being field tested this summer. Another control tactic being researched is to use winter rye as a cover crop and then kill it in late spring with a roller-crimper when the rye is heading. Row crops such as soybean are then planted into the rye mulch. The resulting rye mulch controls nearly 99% of weeds between crop rows. Its only drawback is that summer-growing row crops, like soybean, must be planted somewhat late, which reduces their yield potential. Experiments were continued and new ones planned with scientists from the University of Lleida (Spain) to evaluate weed phenological responses (e.g., timing of shoot emergence and growth) to differing levels of microclimate-derived variables.
1. Air-propelled abrasive grit for organic post-emergence weed control. There is an inadequate arsenal of economically-viable products/tools for effectively controlling weeds in organic annual crop farming operations. ARS researchers at Morris, Minnesota, have developed and demonstrated a new technique of applying abrasive grit propelled by compressed air for post-emergence weed control in row crops. Organic growers and stakeholder groups are interested in developing this technology for field-scale use. Results have aided in securing extramural funds, which have been used to develop a four-row implement prototype that propels corn cob grit (or other grit, such as lime gravel for simultaneous liming) using compressed air through pairs of nozzles aimed at either side of a corn or soybean row.
2. Camelina, a new winter annual oilseed crop for the northern U.S. Farmers in the upper Midwest are in need of winter hardy cover crops that can double as a cash crop. ARS researchers at Morris, Minnesota, have demonstrated that winter camelina seeded in the fall after such crops as spring wheat or soybean survives west central Minnesota's harsh winters and can be produced with minimal agricultural inputs (e.g., fertilizer and herbicide). Winter camelina can serve as a new "cash" cover crop for northern U.S. farmers and information generated from our study will help university extension personnel and crop consultants to educate and guide farmers in producing camelina.
3. Improved timing of desiccant application to hasten sunflower harvest. Even after seed on a sunflower head have matured enough to harvest, often the leaves and stems of plants are too wet to harvest. The longer sunflower sits in the field to dry before harvesting, the greater the likelihood of losing seed yield due to bad weather and bird predation. Therefore, farmers often spray chemical desiccants on sunflower plants to dry them, so that they can harvest sooner. ARS researchers at Morris, Minnesota, along with North Dakota State University researchers discovered that oilseed and confectionary sunflower can be desiccated earlier than previously recommended without losing yield due to seeds not completing maturity at the time of desiccation. Likewise, this potentially allows sunflower producers to harvest earlier, even as much as a week or more, which can significantly aid in reducing seed yield losses due to bad weather and bird damage. These results will assist farmers and crop advisors to make wiser decisions concerning the timing of desiccation and harvest of sunflower.
4. Seed coatings improve emergence of corn and soybean. Even when soil is sufficiently dry, growers avoid sowing corn and soybean in early spring because of the possibility of early-season cold damage to seed and seedlings. This is especially a problem in no-tilled soils, which are slower to warm than conventionally deep-tilled soils. ARS researchers at Morris, Minnesota, in collaboration with Landec Corp., verified that polymer-based seed coatings prevent germination until soils are warm enough to promote safe emergence. Polymer coatings enable seed planting 2 to 4 weeks earlier than normal while protecting seeds from cold damage. This seed coating technology has been used for "early planting" of corn on more than 1,200 farms covering more than 100,000 acres across the Midwest (http://landec.com/applications/seed-coatings-treatments/). This information and technology are assisting growers, crop advisors, and seed industry personnel in making optimal decisions for spring planting of corn and soybean.
5. Planting recommendations for calendula. Most commercial varieties of calendula are for ornamental and medicinal purposes. Oilseed varieties are few, and little agronomic information exists for them. In conjunction with a visiting graduate student from France, ARS researchers at Morris, Minnesota, determined the best planting depth and soil hydrothermal time (HTT) requirements for successful seedling emergence. Best planting depth was 1 to 2 cm, and 89 HTT units were required for 50% emergence. This information is valuable for agronomists associated with specialty seed companies to advise the growers with whom they establish contracts for raising calendula.
6. Post-emergence herbicide recommendation for cuphea. Cuphea is a new temperate climate oilseed crop whose seed oil can be used to replace imported coconut and palm kernel oils. Only a few herbicides are known to be tolerated by cuphea, and in Minnesota and North Dakota where it is currently grown, greater control of Canada thistle and biennial wormwood weeds is needed. ARS researchers at Morris, Minnesota, and Brookings, South Dakota, demonstrated that the herbicide clopyralid (commonly known as "Stinger"), which is highly effective at controlling Canada thistle and biennial wormwood, can be applied to cuphea at rates commonly used in other crops without damaging cuphea plants. This information will be valuable to crop consultants and the specialty seed industry in developing recommendations for growers producing cuphea. Increasing cuphea production in the U.S. will decrease our dependence on foreign imported oil.Gesch, R.W., Archer, D.W., Spokas, K.A. 2012. Can using polymer-coated seed reduce the risk of poor soybean emergence in no-tillage soil? Field Crops Research. 125:109-116.