Key warning sign of screwworms

9:51 a.m. May 21, 2025

WILL THOMAS
Moore County Extension Agent

The New World Screwworm (Cochliomyia hominivorax) is a parasitic fly native to the Americas. This pest is especially dangerous because its larvae feed on the living tissue of warm-blooded animals, including cattle, horses, deer, pets, and even people. The United States successfully eradicated this pest decades ago through a large-scale sterile fly release program.

Still, recent detections in parts of Mexico and Central America have raised concern about its potential return to our region. Effective as of May 11, 2025, U.S Secretary of Agriculture Brooke Rollins suspended live imports of cattle, bison, and horses from the southern border on a month-by-month basis till a satisfactory outcome can be achieved.

Although we haven’t seen any confirmed cases in Tennessee, it’s important to stay vigilant. If this problem were to reach us, livestock owners should carefully inspect their animals for open wounds, especially during the warm months when fly activity increases.

A key warning sign of screwworm infestation is a wound that seems to worsen instead of healing, often accompanied by a foul odor, restlessness in the animal, or deep, rapidly enlarging lesions that may be crawling with maggots. With good control measures, USDA hopes to stop the spread before it can affect our border states and work even further North.

Poison Hemlock

Poison hemlock (Conium maculatum) is one of the most toxic plants in North America. It is common in Moore County, almost anywhere you look. You’ll often find it growing along roadsides, fence lines, pasture edges, and waterways. While its delicate white flowers and fern-like leaves may look harmless, every part of this plant is poisonous to humans and animals alike. Livestock can suffer fatal consequences if consumed; even handling the plant with bare skin can cause irritation in some individuals.

Proper identification is key. Poison hemlock typically grows three to eight feet tall. It is easily recognized by its smooth, hollow stems marked with distinct purple or reddish spots. The leaves are finely divided and have a lacy appearance. Unlike wild carrots or Queen Anne’s lace, poison hemlock gives off a musty odor when crushed, which is another good clue when trying to confirm its identity.

Mechanical and chemical approaches can be used for control. Mowing can help reduce seed production if done before the plant flowers, but it won’t kill the root system, so regrowth is likely. Herbicides such as 2,4-D or triclopyr are most effective when applied in the plant’s rosette stage, which occurs in the fall or early spring.

Spot-spraying individual plants is ideal to avoid harming desirable grasses or forbs nearby. Always wear protective clothing and gloves when handling these chemicals and poison hemlock, and never burn it, as the smoke can be toxic.

Farmland Preservation

On May 12, Gov. Bill Lee officially signed the Farmland Preservation Act, a historic piece of legislation to keep Tennessee’s farmland in production for generations to come. The new law establishes a state-level farmland conservation fund that will support voluntary efforts by landowners to preserve working farms.

One key part of the program is the use of agricultural conservation easements. These legal agreements allow farmers to continue owning and operating their land. However, they restrict future non-agricultural development, ensuring that the land stays in agriculture even if it changes hands down the road.

The Act also allows state dollars to be matched with federal and private funding sources, helping Tennessee stretch its resources and protect more acres. This is especially important because many states already have similar programs. Tennessee has been one of the last in the Southeast to establish a farmland preservation fund.

Over the coming months, the Tennessee Department of Agriculture will work on the program’s rules, application process, and outreach. I encourage farmers, landowners, and rural families to keep an eye out for updates and start thinking about how farmland preservation might fit into their long-term goals.

This isn’t just about protecting land. It’s about preserving a way of life. The Farmland Preservation Act is a big step in the right direction. It’s great to see Tennessee supporting the people who grow our food, steward our natural resources, and carry on the tradition of farming across the Volunteer State.

Market Notes

by Andrew Griffith

Based on Tennessee weekly auction reports, steer prices this week were $1 to $5 higher than last week, while heifer prices were $4 to $5 higher than the previous week. Slaughter cow prices were $2 to $5 higher compared to a week ago, while slaughter bull prices were $3 to $5 higher compared to last week.

Producers who have been actively selling cattle the past few weeks have experienced strong prices for all classes of cattle. Calf and feeder cattle prices have remained strong, while slaughter cow prices have been mostly steady, stronger, and higher than one year ago.

The 30,000-foot perspective of cattle markets is highly positive, as markets have continued to boom. The fear in many market participants’ minds is when the bust will occur. Identifying the bust often requires analyzing the forest and then analyzing some of the individual trees, which means there also needs to be a five-foot view to go along with the 30,000-foot view.

Overall, no industry-wide information indicates a bust in the cattle markets. Still, there is always information that can have a negative influence. One of those negative influences is simply the financial investment of purchasing a single animal.
Producers have been paying nearly $2,000 per head for freshly weaned 550-pound steers, while weaned and vaccinated calves are well over that value.

Similarly, the CME feeder cattle index has 800-pound steers between $2,400 and $2,500 per head. These are challenging values, as managing death loss is even more critical. Thus, as a person evaluates individual trees, there are certainly some signs of symptoms that could negatively influence the market, and nothing has even been mentioned about the concerns related to high retail beef prices.

Given these challenges, the market’s supply side remains the storyline as the 2025 calf crop will be smaller than 2024. Similarly, it will be difficult for the 2026 calf crop to demonstrate any increase relative to 2024 or 2025.

Please let me know if I can assist you at (931)-759-7163.

Will Thomas is an Extension Agent with the Moore County Extension Office.

The U.T. Extension Office of Moore County offers programs to all eligible persons regardless of race, color, age, national origin, veteran status, or disability.