Smutgrass is a real pest. In fact, it just may be the leading problematic weed species in Florida pastures. A 2003 survey conducted by The South Florida Beef Forage Program showed that smutgrass ranked as the second most-problematic weed species at the time. However, since control practices for the leading most-problematic weed at that period—tropical soda apple—have been adopted uniformly all over the state in the 13 years since the survey, smutgrass has likely taken over the top spot. Smutgrass control in perennial grass pastures is not a simple, straight-forward undertaking, but the Extension Services of the University of Florida’s Institute of Food and Agricultural Sciences has published a guide for producers.
Smutgrass is an invasive species that hails from tropical Asia. It is found in two forms in Florida pastures: small smutgrass and giant smutgrass (or West Indian Dropseed), with the latter being the most prevalent in Central and South Florida. Mature smutgrass plants of both forms are unpalatable to livestock, and the plants both produce a large number of seeds, allowing smutgrass to quickly squeeze out bahiagrass, bermudagrass, and other palatable pasture foliage. The one positive about smutgrass is the immature form of the plant is palatable to livestock, offering forage quality equal or greater to bahiagrass.
Read the complete UF/IFAS Smutgrass Control recommendations here for details, but a summary of control options and their positives and negatives include:
- Burning: While burning is thought to increase the germination of seeds in the soil seed bank and thus increase the number new plants, livestock can forage on the emerging plants for two to three weeks.
- Mowing: Mowing is believed to increase the density of smutgrass clumps, but like burning it allows for weeks of grazing on new growth.
- Chemical control: Studies have shown the application of Velpar to be effective and cost-effective if at least 50 percent of the field is infected with smutgrass (except when aiming to prevent smutgrass infestations). However, rain or watering is very important during the two weeks following application, so it’s recommended for application from June to September. Velpar use is not recommended within 100 feet of oak trees or with floralta, stargrass, or mulato grasses. Its use also means a 38-day haying restriction, but no grazing restrictions if the application rate is below 4.5 pt/acre (1.13 lb hexazinone/acre).
- Complete renovation of the pasture: Generally, this is recommended if smutgrass infests 80 percent or more of the field.
Griffin Fertilizer is committed to helping both growers and ranchers make sound agronomic and economic decisions in order to maximize the health of their grove and pasture. As a full-service custom dry & liquid fertilizer blender and crop protection product distributor, we will continue our mission to further advance Florida agriculture.
For questions or concerns about your farm or pasture, contact us and one of our team will be in touch.