With hay cutting season upon us there are a few things to keep in your forethoughts. Bermuadagrass Stem Maggot is a relatively new pest to this area of the state.  This pest only infests bermudagrass and stargrass.  The fly, which is yellow with a black head, lays its eggs within the stem of the bermudagrass plant.  Once the egg hatches the larva, or maggot, moves to the last plant node and consumes the plant material within the stem.  This stem damage results in the death of the top two to three leaves while the rest of the plant remains green. This gives a stand of bermudagrass the appearance of frost damage.

Damage caused by the bermudagrass stem maggot (Photo courtesy of Richard Waligura, Waller County, TX)

If damage is found within 1 week of the normal harvest stage, proceed to harvest the crop as soon as weather conditions allow.  The damaged crop should be cut and baled and removed from the field as soon as weather conditions allow.  Leaving the damaged crop in the field will only compete with any attempts by the plant to regrow.  This will decrease the opportunity for the next cutting will have to accumulate dry matter.  A foliar application of a pyrethroid insecticide labeled for bermudagrass can control the bermudagrass stem maggot.  However, guidelines on the economic return on controlling this new pest and timing of and frequency of insecticide treatments have not been clearly defined.

For more information contact Chelsea Dorward at the Bosque County Extension Office, 254-435-2331 or chelsea.dorward@ag.tamu.edu