Multifunctionality of Cover Crops in South Texas: Looking at multiple benefits of cover cropping on small farms in a subtropical climate

View the project final report

Commodities

• Agronomic: millet, oats, sorghum (milo), grass (misc. perennial), hay

Practices

• Animal Production: feed/forage
• Crop Production: cover crops, nutrient cycling, application rate management
• Education and Training: focus group, on-farm/ranch research, participatory research
• Farm Business Management: budgets/cost and returns
• Pest Management: allelopathy, weed ecology
• Production Systems: transitioning to organic, agroecosystems, organic agriculture
• Soil Management: green manures, organic matter, soil analysis, soil microbiology
• Sustainable Communities: local and regional food systems, partnerships

Situated in deep South Texas, the Lower Rio Grande Valley (LRGV) is considered one of the most productive agricultural regions in the southern US. With the highest concentration of organic farms in the state (Hidalgo county), the LRGV has a strong potential to be a leader in sustainable agriculture. However, not much research in sustainable agroecosystem management has been conducted in this subtropical region, where pests and weed pressures are immense and year-round, and, as such, farmers are looking for viable strategies to deal with these barriers. Finding management practices that comply with organic certification and increase the health of the agroecosytem and the farmers working the land are increasingly pertinent. Cover cropping, or the intentional planting of non-cash crop vegetation, can serve multiple functions in an agroecosystem by decreasing environmental pollutants that originate from the agroecosystem, reducing inputs needed for crop production, and potentially decreasing on-farm costs for farmers—overall increasing the sustainability of the farm. To date, there is no research on appropriate cover-cropping strategies in this important agricultural region. The aim of this research was to generate baseline information on the potential of different cover crops species to increase soil organic matter, nitrogen content, impact on beneficial soil microbes (mycorrhizal fungi), and weed suppression. The cover crops included in this study were: tillage radish (Raphanus sativus), winter rye (Secale cereal), lablab (Lablab purpureus), sunn hemp (Crotalaria juncea), sudangrass (Sorghum drummondii), and pearl millet (Pennisetum glaucum). Results from this study indicate that these cover crops have the potential to enhance ecosystem services on agricultural lands in the LRGV by increasing soil organic matter, nitrogen concentration, weed suppression and the mycorrhizal fungi population in the soil.

1. Identify summer cover crops suitable for South Texas and the rest of planting zone 9b,
2. Determine which cover crops provide the most multifunctional benefits for farmers in South Texas by assessing: (a) weed suppression; (b) soil fertility; and (c) beneficial soil microbes,
3. Assess the economic viability for small growers in South Texas to use cover crops in their land management plan,
4. Improve access to information on cover crops so that agricultural professionals can make better recommendations and producers can make better management decisions.