6 Best Cattle Fly Control Systems For Premium That Old Farmers Swear By

You can tell fly season has arrived just by watching your cattle. Instead of grazing peacefully, they’re bunched up, stomping their feet and whipping their tails constantly. That isn’t just an annoyance; it’s a direct assault on your herd’s health and your farm’s bottom line. Effective fly control is one of the highest-return investments you can make, protecting your animals from stress, disease, and significant weight loss.

Disclosure: As an Amazon Associate, this site earns from qualifying purchases. Thank you!

Understanding the True Cost of Cattle Fly Stress

Flies are more than just a nuisance; they are a tax on your herd’s productivity. Horn flies, which cluster on the backs and sides of cattle, can take up to 30 blood meals a day. This constant biting and blood loss causes immense stress, leading cattle to burn energy fighting flies instead of gaining weight. Studies show that heavy horn fly infestations can reduce calf weaning weights by 15 to 50 pounds.

Face flies, while they don’t bite, are major vectors for pinkeye. They feed on the secretions around an animal’s eyes, transmitting the bacteria that cause this painful and potentially blinding infection. Then you have stable flies, which deliver a nasty bite primarily to the legs and belly, causing cattle to bunch up and stop grazing. For a small operation, the cost of a single vet visit for pinkeye or the lost weight on just a few calves can easily exceed the cost of a full-season fly control program.

The key is to see fly control not as an expense, but as an essential part of animal husbandry. A stressed, uncomfortable animal will not perform well, whether you’re raising for beef or dairy. By managing the fly population, you are directly investing in better weight gain, higher milk production, and a healthier, more contented herd.

CyLence Ultra Tags for Season-Long Protection

Ear tags are the classic set-it-and-forget-it solution for pasture cattle. Once you get them in, you have months of protection without having to handle your animals again. CyLence Ultra Tags are a top-tier choice because they use a potent combination of two active ingredients, beta-cyfluthrin and piperonyl butoxide, offering a powerful defense against both horn flies and face flies.

The tags work by slowly releasing a small amount of insecticide that spreads across the animal’s coat through movement and grooming. This creates a protective barrier that repels and kills flies for up to five months, effectively covering the entire fly season in most regions. They are particularly effective against pyrethroid-susceptible horn flies, which are often the biggest problem for grazing cattle.

The main tradeoff is application. You need a headgate or chute to safely restrain the animal while you apply the tag, which can be a significant undertaking on a small farm. More importantly, you must rotate the chemical class of your tags each year. If you use a pyrethroid-based tag like CyLence one year, switch to an organophosphate or another class the next. This is non-negotiable if you want to prevent insecticide resistance from rendering your tags useless in a few seasons.

Ultra Boss Pour-On for Broad-Spectrum Control

Pour-on insecticides offer a great balance of effectiveness and ease of application. Ultra Boss is a workhorse product that many old-timers rely on for its broad-spectrum control. Applied in a single strip down the animal’s backline, it spreads over the skin to kill horn flies, face flies, stable flies, and even biting and sucking lice.

The biggest advantage of a pour-on is its versatility. It’s faster to apply than ear tags if you have a simple alleyway, and it provides control over more than just flies. This is especially useful in the fall or winter when lice can become a problem. The application is straightforward, but it’s crucial to use the correct dosage based on the animal’s weight for it to be effective.

However, pour-ons don’t offer the season-long protection of an ear tag. You’ll typically get about three to four weeks of solid control before needing to reapply, meaning you’ll be working your cattle more often. Its effectiveness can also be reduced by heavy rain shortly after application. It’s an excellent tool, but one that requires more frequent management than tags.

The Lewis Cattle Oiler for Self-Application

For a truly low-labor solution, nothing beats a good cattle oiler. The Lewis Cattle Oiler is a simple, nearly indestructible piece of equipment that lets your cattle treat themselves. It consists of a reservoir that you fill with an insecticide-and-oil mixture and a system of wicks or a hanging mop that the cattle rub against.

Cattle have a natural instinct to scratch and rub, and they will quickly learn to use the oiler to get relief from flies. As they push against the applicator, a small amount of the insecticide is applied to their faces, backs, and sides—exactly where they need it most. This provides consistent, on-demand application without you ever having to round up the herd.

The initial investment is higher than a box of tags or a jug of pour-on, but a well-made oiler will last a lifetime. You control the type and concentration of insecticide, allowing you to easily rotate chemicals to fight resistance. The main task is simply keeping the reservoir filled. For a pasture-based hobby farm, an oiler is one of the smartest long-term investments you can make for fly control.

Altosid IGR for Manure Management Control

The most effective fly control programs attack the problem from multiple angles. Altosid IGR (Insect Growth Regulator) is a feed-through product that stops flies before they even hatch. It works by disrupting the fly life cycle in the one place they are guaranteed to be: fresh manure.

Altosid is typically mixed into mineral or feed. The cattle ingest it, and it passes through their digestive system into their manure. The active ingredient is harmless to the cow but prevents fly larvae in the manure from developing into adult flies. This method doesn’t kill existing adult flies, but it dramatically reduces the emergence of new generations.

This is a proactive strategy, not a reactive one. You must start feeding it 30 days before the first flies appear and continue throughout the season. Because it doesn’t affect adult flies that fly in from neighboring properties, it must be used as part of a larger system. Pairing an IGR with ear tags, a pour-on, or an oiler creates a powerful one-two punch that controls adult flies on the animal and prevents new ones from ever taking wing.

Starbar Fly Terminator Pro for Area Reduction

Sometimes you need to reduce the sheer number of flies in a concentrated area, like around a barn, loafing shed, or water trough. That’s where a high-capacity trap like the Starbar Fly Terminator Pro comes in. This isn’t about treating your cattle; it’s about reducing the overall fly pressure on your property.

These traps use a powerful attractant that flies can’t resist. They fly into the jug-style container through a one-way entry and become trapped. A single trap can catch tens of thousands of flies, and seeing it fill up is one of the most satisfying jobs on the farm. It’s a simple, effective, and non-chemical way to knock down the local fly population.

It’s crucial to understand the role of these traps. They are a supplemental tool, not a primary control method for cattle in a large pasture. You also need to place them strategically—away from your house and barn doors. Their job is to draw flies to the trap, so you want to pull them away from areas where people and animals congregate.

Spalding Fly Predators for Natural Prevention

For those looking for a more natural, non-chemical approach, Spalding Fly Predators are a fantastic biological control method. These are not predators in the way a hawk is; they are tiny, gnat-sized insects that do not bite or sting humans or animals. Their sole purpose is to destroy the next generation of pest flies.

You receive a shipment of Fly Predators in their pupal stage and release them near manure piles and areas where flies breed. The predators seek out and destroy developing fly pupae, killing them before they can hatch into adults. This breaks the life cycle from the ground up, using nature to fight nature.

Like IGRs, this is a preventative measure that must be started early in the season before the fly population explodes. It requires a commitment to releasing new predators every few weeks to maintain a healthy population. Fly Predators won’t solve a problem with adult flies that are already plaguing your cattle, so they are best paired with fly traps to catch the adults while the predators work on preventing new ones.

Creating a Rotational Plan for Your Operation

There is no "one-size-fits-all" solution to fly control. The most successful and sustainable approach is an Integrated Pest Management (IPM) plan that combines multiple methods and, most importantly, rotates chemical classes to prevent resistance. Simply using the same product year after year is a recipe for failure.

A smart rotational plan attacks flies on multiple fronts. Consider a multi-year strategy:

• Year 1: Use a pyrethroid-based ear tag (like CyLence) for on-animal control and place fly traps around the barn to reduce local pressure.
• Year 2: Switch to an organophosphate-based ear tag to combat pyrethroid resistance. Add an IGR mineral to your feeding program to suppress larvae development in the manure.
• Year 3: Remove tags altogether and rely on a cattle oiler with a different chemical class, continuing the IGR mineral and fly traps.

This kind of thinking keeps the flies off balance and your control methods effective. By targeting adults on the animal, larvae in the manure, and populations in high-traffic areas, you create a comprehensive defense. A thoughtful, rotational plan is the difference between constantly fighting a losing battle and keeping your herd calm, healthy, and productive all season long.

Ultimately, managing flies is about more than just comfort; it’s about protecting the health and productivity of your herd. By layering different strategies and rotating your tools, you can build a resilient system that works for your specific operation. A proactive, multi-pronged approach is the foundation of effective, long-term fly control.