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Broadleaf Signalgrass (Brachiaria Platyphylla)

Crop Impacts: Corn and Soybeans

Broadleaf Signalgrass 1

About Broadleaf Signalgrass:

Broadleaf Signalgrass is an annual grass that is native to North America with its most active growing period in the spring. The corn yield can be reduced by 25% due to the competitive nature of this grass.

Family: Poaceae ⁄ Gramineae family (grass family)

Broadleaf Signalgrass 2 Broadleaf Signalgrass 3

Broadleaf Signalgrass Scouting and Prevention:

The Broadleaf Signalgrass can grow up to 3 feet, depending on growing conditions, although it typically grows lying parallel to the ground. The leaves are rolled at the base and are wide with a few hairs on them. The leaf blades have a blunt edge, are about 4 to 8 inches long and can be rough or smooth. Broadleaf Signalgrass produces seed heads that are about 12 inches long and 4 inches wide. The seeds of the Broadleaf Signalgrass heads start to form from July to September.

Common locations

  • - Agronomic crops
  • - Corn Fields
  • - Soybean Fields
  • - Sandy soil


Prevention of Broadleaf Signalgrass is less expensive and less time-consuming then trying to control it. Make sure when you seed a new area you do so with certified weed-free seeds. If there is an infested area on your property, be sure to drive around instead of through it. Make sure to give all equipment that has been in infested fields a good clean to make sure no seeds are transferred.

Broadleaf Signalgrass Control:

Cultural Control

Do not panic if you find Broadleaf Signalgrass in your fields. Here are a few general suggestions to protect your crops from weeds:

  • - Make sure you have high-yielding varieties of plants that are adaptable
  • - The field should be planted in narrow rows with high plant population as soon as ideal soil and weather conditions are met
  • - Scout fields on a regular basis
  • - Do the recommendations given to you by the soil test

Chemical Control

With the application of Accent, a post-emergent herbicide, it can provide about 90% control over Broadleaf Signalgrass. Celebrity Plus, Celebrity, and Basis Gold are other herbicides that give good control when it is applied while Broadleaf Signalgrass is still young. Overall, the best time to apply herbicides to Broadleaf Signalgrass is when they are about 1 to 2 inches long.

Latin / Alternative Broadleaf Signalgrass names:

  • - Brachiaria Platyphylla

Additional Broadleaf Signalgrass Resources