See tips for Florida ranchers for controlling armyworms in Florida grazing pastures to keep this destructive pest at bay.

In a past blog, we shared information related to scouting for and identifying armyworms, a group of caterpillar species that can be very destructive to many different crops, including a number of forages. The information was from a UF/IFAS blog that advised “armyworms can significantly impact the health of your pastures and hayfields.” Unfortunately, “armyworms prefer well fertilized grasses,” the blog warns, and they can devastate your well-tended forages in a matter of weeks, leaving your herd with nothing. See control options below from the blog to ensure your forages are saved for your cattle.

Controlling Armyworms

The blog shares these tips for signs of armyworm infestation:

  1. “Leaf Damage: Irregular holes in leaves, starting from tips and edges.
  2. Wilting or Browning: In serve cases, pastures may appear wilted and turn brown.
  3. Frass: Greenish-black droppings found on the ground.
  4. Patchy Areas: Infestations can create uneven growth patterns in the pasture.”

Populations can explode and multiply quickly, so don’t wait to enact control measures if you spot this pest. Options for armyworm management include:

  1. “Cultural Practices:
    • Mowing/Grazing: Mowing or grazing can reduce feeding sites for caterpillars.
    • Cutting Hay: Cutting hay can help protect your crops and reduce the need for chemical controls.
  2. Biological Control:
    • Encourage natural predators like birds and beneficial insects.
  3. Chemical Control:
    • Integrated Pest Management (IPM): Combine methods for effective control while minimizing chemical use.
    • Insecticides: Use targeted insecticides and consider mixing (e.g., pyrethroids are fast acting and diflubenzuron products provide residual control). If rain is in the forecast, consider a rainfast product like Vantacor, Shenzi, or Besiege. Always read the label first before purchasing and applying to be sure the product is labeled for intended use and forage crop. To ensure caterpillars and insecticide contact, applications should be made in the morning or evening. Always follow all PPE (Personal Protection Equipment) guidelines when applying insecticides.”

See the UF/IFAS blog for a chart of insecticides available to control armyworms in Florida grass pastures and hayfields.

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.