Hay crops showing symptoms of freezing sounds nonsensical in a Texas June, yet, for a few local producers, that was exactly what they saw in their crop. Eventually the real culprit for the hay damage, the Bermudagrass Stem Maggot, was identified.
Before AgriLife extension agents confirmed the presence of the maggots, Wharton area hay farmers reported the leaves of their crop had oddly turned brown and white and the stems had stopped growing. Symptoms like these can indicate a frost, herbicide drift – when chemicals used to kill unwanted weeds land on crops instead – or lack of fertilizer.
“This relatively new pest of Bermudagrass hay fields is not new to Wharton County, it’s just new to hay growers in the Wharton area,” Extension Agent Corrie Bowen said via a press release.
Bermudagrass Stem Maggots are native to parts of Asia and were identified by the Wharton County AgriLife Extension Office in Wharton area hay fields in early June. The maggots, which eventually evolve into small flies, have been in Wharton County since 2017, in Texas since 2013 and in the US since 2010.
These insects feed on hay stems before growing into adult flies. Texas researchers estimate that 8.9 pounds of hay yield per acre was lost for every one percent of damaged hay stems. The amount of damage the maggots do to crops can vary.
“If (the infestation) is in pasture, it’s probably going to be alright,” AgriLife Extension Agent Kate Crumley said. “If it’s in a hay patch and you’re planning on cutting that, you can have some pretty significant yield reduction. Depending on how severe the infestation is.”
Other factors affecting the damage include the growing conditions for the hay. Soil that is dry and less fertile is more susceptible to damage, according to Bowen. The pest is known to damage varieties of hay that are common in Wharton County, including alicia and coastal hay while courser-stemmed varieties like tifton 85 are less likely to be infested.
Whether the insect population will become more prevalent in the Wharton area will depend on the weather this year,