Texas ranks first in number of farms and third in total agricultural production in the U.S. However, the state lags behind in organic crop production. The low rate of adoption of organic farming for grain crops such as corn and sorghum has been a major bottleneck for expansion of the organic livestock sector in this state. The specific goals of this study are based on our interactions with farmers and other stakeholders in the region. Collectively, these discussions have shaped the goals and objectives of the project. Our goals are: (1) Conduct research and onfarm demonstrations in a partnership between scientists and stakeholders for greater understanding of the influence of cover cropping in no-till organic systems on soil fertility, weed dynamics, wateryield relations, and soil health, (2) Develop best management practices that optimize both agricultural profitability and ecosystem services in transitioning cropping systems (corn and soybeans), (3) Develop an educational and outreach program for efficient transfer of project results to the various stakeholders and organize training efforts on the certification process, farm plan development, environmental benefits, and best management strategies while transitioning to organic production. Through this project, we will address some of the critical needs of farmers and other stakeholders in Texas who plan to adopt organic farming.
- Conduct research and onfarm demonstrations in a partnership between scientists and stakeholders for greater understanding of the influence of cover cropping in no-till systems on weed dynamics, soil-water relations and crop yield for organic grain cropping systems (corn and soybean).
- Develop best management practices that optimize both agricultural profitability and ecosystem services in organic cropping systems (corn and soybean).
- Develop an educational and outreach program for efficient transfer of project results to the various stakeholders and organize training efforts on organic certification process, farm plan development, environmental benefits, and best management strategies for cover crops and tillage practices while transitioning to organic
A three-year organic cover crop system experiment was established during the summer of 2017 at College Station, TX. This is managed according to NOP-guidelines with large buffer zones, as land will be transitioned to certified organic. The experimental design is a randomized block design with four replications for corn and soybeans, both crops grown each year in rotation. Cropping systems will focus on corn and soybeans to provide contrasting planting window requirements. Yield goals for system development are 125 bu/acre for corn and 40 bu/acre soybeans. Experimental units are 4 rows wide (10 ft) by 150 ft in length. The main soil type is clay. We imposed six experimental cover crop systems for each main crop to evaluate: (a) cover crop productivity and termination efficacy, (b) weed suppression potential, (c) nutrient balance (d) water use (e) yield and (f) economic return.
Cowpea (Vigna unguiculata L.) cover crop was planted on September 7, 2017 proceeding planting of cover crops for corn or soybean rotations. Biomass of cowpeas was measured and N content determined to estimate N input. The cowpea was shredded and incorporated before planting of fall cover crops. The experimental cover crop systems included six contrasting species planted on November 7, 2017 proceeding corn or soybean. Cover crop selections included Haybet Barley (Spring), Glenn Hard Red Spring Wheat, TAM EXP Oats, Rye/Vetch, Elbon Rye, and Fannin Hard Red Winter Wheat. Cereal rye has been investigated extensively in cover cropping and organic systems. This will serve as a base-line for comparing results to other regions and systems. Cover crop biomass was recorded.
Composted turkey manure was applied to provide 60 lb N/ acre before planting corn. Corn was planted using Prairie Hybrid PH7387 at 79,040 seeds/ha on 3/22 and replanted on 4/13. Replanting was required due to poor stands as a result of insect damage from wireworms and seed maggots. Soybean was planted on 4/6 using Progeny Seed P4910 at 345,800 seeds/ha.
Decomposition of cover crop residue was estimated using lab and field incubations of residue. Litter bags with contrasting residue were installed in the field and harvested on 4 dates to estimate mass loss of residue. Lab incubation with soil were conducted to estimated CO2 release and mineralization of N from residues.
Cover crop planting in 2018 was delayed until 11/30 due to excessive rainfall in the region. The target planting date was in September. All cover crops established good stands. Cool and wet weather combined with later
Cover crops were terminated in the spring of 2018 proceeding planting of grain crops. Biomass estimates were obtained at the time of termination. Ratings for cover crop termination, planting condition and weed suppression were recorded. Weed suppression was evaluated several times during 2018. Despite variation in cover crop performance, no harvestable grain was produced for corn or soybean. Replanting of corn pushed growth periods into unfavorable weather. Soybean biomass remained low all year and did not produce harvestable grain.
Study results were shared at several producer education events. With the project being in progress. General considerations for cover crop use and logistics surrounding cover crops in Texas were discussed.
Graduate student education is a component of this project. Student presented research results at regional and national meetings.
Extension education material is currently under development.
Educational & Outreach Activities
Results from the first year were shared at county Extension meetings and professional conferences.
Project is in progress. Educational components are under development. Changes in knowledge, etc., will be documented as training events occur.
With one year of the study complete, we observed significant differences in cover crop performance. These results should lead to better recommendations for Texas producers. Additional data and improved biomass and grain yields in subsequent years is expected to strengthen results.