Rodolfo Gonzalez | AP
Miller, who lost the March Republican primary in a bid for a fourth term despite winning President Donald Trump‘s endorsement, has repeatedly slammed the USDA’s response after the parasitic pest was detected in Texas last week. He has argued that the federal department acted too slowly to contain the pest and ignored a response mechanism that he has pushed.
At a Monday news conference in Texas on the USDA’s response, Rollins was asked about Miller’s recent assertion that ranchers would not report a case on their farms over fear that the government would impose a quarantine.
“That is a very unserious comment, from perhaps an unserious ag commissioner with just a few months left,” she said of Miller. “It is also a very dangerous suggestion.”
The rift between Rollins and Miller effectively pits the top agricultural leaders in the country and in the state currently affected by the outbreak against each other. And it comes as the Trump administration races to contain the screwworm, which threatens to thin out an already weak cattle herd and further raise beef prices.
Rollins, also a Texan, slammed Miller in an appearance on CNBC’s “Squawk Box” earlier Monday.
“It’s very unfortunate what the Texas ag commissioner has been saying, I’ve known him for a long time,” Rollins said. “He lost his primary as the incumbent a few months ago, and has had lots of crazy ideas for a long time.”
Underscoring the spat is that Miller, a former rodeo cowboy who was once considered for Cabinet positions in the Trump administration, was endorsed by Trump just months ago before losing his primary to the Texas Gov. Greg Abbott-endorsed candidate, Nate Sheets. Miller has been a longtime Trump surrogate, once threatening to go after “RINOs” — shorthand for “Republican in name only” — who “slipped the noose” in the 2024 elections, and his criticism is a rare rebuke of Trump’s administration from a close ally.
In endorsing Miller, Trump said he is a “MAGA Warrior who has been with me from the very beginning.”
He urged the USDA to implement the Screwworm Adult Suppression System, or SWASS, which was developed in the 1970s and combines insecticides with sterile flies. USDA is currently deploying sterile flies.
Miller appealed directly to Trump, asking him to “take direct control of this response” and “deploy SWASS immediately, and throw every available federal resource at this threat before it becomes a full-blown agricultural disaster.”
Sid Miller, Texas Commissioner of Agriculture, takes a photo during an event to “Celebrate the Implementation of the Dietary Guidelines for Americans” at the Health and Human Services Headquarters on February 11, 2026 in Washington, DC.
Michael M. Santiago | Getty Images
USDA is urging any cattle producer who detects screwworm to immediately report it, as it races to contain the pest, which can be deadly to cattle if left untreated. The pest spreads via a fly that lays eggs in an open animal wound. The eggs hatch into larvae, which then eat the flesh of the affected animal.
An infestation is treatable if detected early enough, and the pest was eradicated from the U.S. in the 1960s. It does not represent a threat to food safety.
The USDA is currently implementing its screwworm playbook, similar to the one used to eradicate the pest in the past. That includes quarantine zones, increased trapping, surveillance and outreach. The USDA is also releasing sterile flies over the area, which mate with female flies and produce infertile eggs to snuff out the parasite.
USDA is racing to ramp up the production of sterile flies, with Rollins on CNBC saying the administration was working at “Trump speed” to address screwworm. That includes breaking ground on a new facility to produce sterile flies and opening a new dispersal facility earlier this year.