06/09/2026
Robertson County AgriLife Extension Service Ag Newsletter - June 2026
Currently, we are facing several threats and challenges in the Ag Industry. The main 2 threats I want to discuss today are Pasture Mealybugs and New World Screwworm. I have attached several factsheets and some current information being released by us in Extension, the Texas Animal Health Commission and the USDA. I will try and update you all as we continue to get information on these current issues.
Pasture Mealybugs
We have seen these pretty prevalent around Robertson County this early summer this year and we had them in the county last year actually as well. The mealybugs cause a “pasture dieback” kind of look. Your pasture will suddenly “not look quite right” or looks worse than it actually should. You will see some yellowing, appear stressed when it shouldn’t be, or coloring going to reddish/purplish and then eventually brown as it deadens. The key is detection and monitoring pastures regularly: 1) look for areas that are not looking like the rest of your hayfield or pasture; 2) yellowing of color or a reddish/purplish look to leaves; 3) inspect the soil surface and thatch layer for bugs as you pull grass back ad push it aside to look down into your grasses; 4) treatment needs to be done before reddish color and brown colors – need to treat when you see yellowing.
The mealybugs have been seen in 50 counties currently in Texas. They prefer the highly precipitated areas with rain over 20” yearly. They don’t like the dry weather. They also prefer hot and humid weather, high biomass pastures, actively growing grasses, and lot of green leaf tissue. They have been found in all improved grasses, but also in Bahia grass, johnson grass, natives like bluestems and even old world bluestem WW B Dahl grass. The males are tiny with wings but they are non-feeders. The adult females are not winged and typically 2-5 mm in length. They are white , some being a pale yellow, and have a lot of fringe like fuzz hanging off of them. Females can produce 4 instar nymphs, so we are looking at around 3 generations per year. The main culprit to the damage to our pastures comes from the nymphs. These little suckers feed on the leaf tissue of our grasses and produce a toxic saliva that is toxic to our plants. This is what is killing our grasses.
It’s best to try and keep your pastures at optimum health. Stresses grasses/pastures will die quicker. Fertilize normal, irrigate if/when possible as irrigated grasses tend to decline more slowly than non-irrigated grasses, promote rapid growth and good growing conditions, avoid moving equipment to non-infected pastures, and if you do use equipment in infected pastures/fields, then spray that equipment down with a pyrethroid. Suppression methods are mowing, cutting, and grazing. Fall/Winter burning can also be an option and then establishing action thresholds. Treatments of hay field if within a week or so of cutting: Go ahead and cut it and roll it up. Lot of research and result demonstration trials are currently being done to
determine which insecticides will be most optimum in controlling this bug. Research will have to be done to see if movement can occur after hay has been rolled up. I would think I’d hesitate to move hay from infected fields and transport somewhere else for a time period. More research will need to be done to determine all of this. There are multiple trials being done across the state and some locally here as well and we will continue to search for answers. There is currently NO insecticides labeled for use in Texas pastures that are effective.
You can sign up for regional weekly IPM audio updates at: https://www.texasinsects.org/agriculture-audio-updates-home.html
They have these split into the different parts of the state.
As I continue to learn new information, I will pass along to all of you.
New World Screwworm (NWS)
With New World Screwworm confirmed in Texas, I am getting a lot of questions and know you will too. There is a lot of bad information out there. Please only refer to valid sources of information. There is reports today of a dog in Andrews County that was recently in New Mexico and a goat in Gillispie County.
Every and anything you'd want to know about NWS will be here: https://agrilifeextension.tamu.edu/new-world-screwworm-fact-sheet/
There is a list of approved products (which changes often) https://www.fda.gov/animal-veterinary/safety-health/animal-drugs-new-world-screwworm
7 Hour CEU Farm and Ranch Management Program
We will have new information presented in October at our 7-hour CEU Program held here in Franklin. The date will be October 26, 2026, at the Pridgeon Community Center in Franklin. If anything, new arises and we need an earlier program, we will certainly set something up and get that information to all of you. Be safe out there and monitor your fields and livestock regularly.
David W. Groschke
County Extension Agent – AG/NR
Robertson County
Texas A&M Agrilife Extension Service
(979) 828-4270
In response to the increased activity of the new world screwworm, Texas A&M AgriLife experts provide research-backed information to Texas.
