Horse flies are a very large family of biting flies. Scientifically, horse flies belong to the family Tabaninae and the order Diptera – True flies. In the subfamily, Tabanidae are both deer flies and horse flies. Both groups are biting flies. The estimated number of species of biting fly worldwide is 4,500 species. 
How to Spot a Horse Fly
Horse flies are big like bumble bees, wasps, and honey bees. They range in size from 3/4 of an inch to 1 1/4 of an inch. They have bristle-like hairs, and their bodies are either all black or a mixture of black and yellow. One of the first things that you notice about horse flies is their very lovely eyes, which are a kaleidoscope of color. If you are close enough to see their eyes, then you might also know their other all-too-common trait – their bite.
Why Do Horse Flies Bite?
Not all horse flies bite. It is only the female. She bites because she needs the high-quality nutrients found in blood to finish her reproductive cycle. A female horse fly lays 100-800 eggs. A few species may lay clutches of eggs 203 times per year, but in general, most female horse flies lays one clutch of eggs per year.
For the female horse fly, reproduction is the biggest event of her life. It also takes a lot of energy to produce and lay 800 eggs. Blood, whether human or animal is a rich food source for her. In short, your blood supplies the energy that helps create the next generation of horse flies.
The Evolution of a Predator
In science, we look at the flow of energy and how organisms change to find the more efficient way to survive while meeting all of their needs to reproduce. Because biting female flies require a blood meal to finish their reproductive cycle, their mouthparts evolved into very efficient tools that meet their needs.
To feed is dangerous. When the female horse fly bites you or an animal, she risks her life and her contribution to the next generation of horse flies. Her evolution is remarkable because it takes the risk of death into account. In short, she is an efficient feeder.
The mouthparts of a female horse fly are a weapon-grade tool. They consist of a pair of scissor-like mandibles which she plunges into flesh. As she does, they open like a pair of scissors or shears, thus expanding the wound. Even before she stabs you, glands begin to secrete an anticoagulant so that your blood flows quickly to the surface.
She can stab you, drink your blood, and fly off in such an efficient way that she usually avoids your hand as it tries to smash her. Her evolution is remarkable, and her bite is quite painful. In fact, a few horse flies can create mass panic in livestock or groups of humans. An infestation of biting flies has no problem clearing a beach of people. In fact, the University of Kentucky’s Entomology Department  estimates that heavy infestations of biting flies can dramatically diminish the production of livestock, such as dairy cattle, beef cattle, and horses.
Despite Modern Technology, Biting Flies Are Still a Pest
Mankind has tried to eradicate biting flies and still, they persist in being a menacing pest. The biggest reason behind our failure to kill off biting flies is that in the early attempts, we failed to understand them enough to deal with them. We thought that they were a species of flies, like the mosquito, which spends part of their lifecycle as aquatic insects. So we poisoned the bogs and wetlands with pesticides hoping to kill them. We did not succeed because horse flies are dependent upon laying their eggs in bogs or streams. In fact, the larvae are found in a variety of aquatic habits including livestock water troughs, hot springs, and small ponds. While most species are purely terrestrial, some have an aquatic phase to their lifecycle. People invented traps to lure in the females and then destroy them. Many of those designs did not work either. These flies are not like scavenger flies – blow flies, flesh flies, and bottle flies. They do not eat the dead, but the living so they do not rely on smell to find food. They rely on sight to track and target their prey, so baited traps did not work to subdue this wretched pest.
A tool that does work is a new type of trap that uses the biting flies method of hunting to lure them in and then destroys them. Biting flies hunt by sight. They look for large, dark objects that move slowly. Think about how deer, cattle, and horses graze. Consider how we mend fences, plow fields, and enjoy the outdoors. We all – cattle, horses, deer, elk, and man – slowly meander while we eat, drink, and be merry. The Fly Cage mimics those slow moving, grazing-like motions to draw in the female horse flies. When she tries to investigate, she becomes trapped and then dies. This new way of controlling biting flies works because it uses the biting flies own evolutionary advantages against them. It does not rely on pesticides or smelly baits. It uses the subtle movement of grazing animals, and it does its job well.
Yellow flies are members of the deer fly family. They are big biting flies. In the South, they call them yellow flies. Elsewhere they are also known as June flies, stouts, and deer flies. No matter what you call them, their bite is painful, bloody, and almost a way of life.
Scientifically, deer flies are in the genus Chrysops and the family Tabanidae. Yellow Flies are large. That is why the Canadians call them Stouts. They get their name – yellow flies -in the South because they are mostly yellow in color. Many of the deer flies are dark or banded to look somewhat like a mad cross between a bumble bee and a yellow jacket. It does not matter where you are from, if the female yellow fly has ever bitten you, then you understand what a painful pest these flies are.
The Bite of Yellow Flies
The bite from a yellow flies is painful enough to ruin your outdoor adventures. Their mouthparts have sharp, spade-like mandibles which they use to render flesh. It is the females that bite because they need the protein found in warm blood to finish their reproduction cycle.
Producing 50-300 eggs takes a lot of energy. Blood is rich in nutrients and protein. That is why the mouth parts of yellow flies are so effective. As they plunge their mandibles into your flesh, they deposit an anticoagulant. The anticoagulant not only keeps your blood gushing out it also is what causes the bite to hurt so much. Well, not that having spade-like mandibles jabbed into your flesh is pleasant.
The soft parts of their mouths sponge up the upwelling blood quickly and efficiently. They can stab you, drink your blood, and be gone before you can prevent the bite. Don’t worry if your slap missed her. She or one of her many sisters will be back for more. The University of Kentucky estimates that the bite from one deer fly takes about 1-cc of blood from the victim. With about five quarts of blood, humans are a walking buffet for yellow flies.
Resistance is Futile
For centuries we have tried to get rid of biting flies. In places where they thrive, like the South, their infestations are so extreme that they damage livestock production. Ranchers, farmers, and outdoor enthusiasts have tried to control deer flies using pesticides. The result was that few of the flies died and the rest became nearly immune to pesticides. The problem is that deer flies are predatory flies. They do not hunt the dead as blow flies do. They do not need to smell you to find you. While their antennas do track carbon dioxide, they use their eyes as their primary tool for locating prey.
To truly control Yellow flies you have to understand how they hunt and then use that information against them. That is what the Fly Cage does. It mimics the movement of big game animals such as deer, elk, moose and livestock such as cattle, horses, and goats. If you think about how these animals move – at a slow stationary gate as they graze – then you understand the methodology for successfully attracting biting flies. Man moves in much the same way. We slowly fix the fence, plow the field, mow the lawn. We are prime targets for biting flies. The Fly Cage attracts yellow flies and then kills them. It uses their hunting behaviors as a weapon to destroy them, and it works.
Horse fly and deer fly, which include yellow flies and green heads are in the family Tabanidae. This group of biting flies is a serious pest to cattle, horses, other forms of livestock, pets, and humans. They get their name because they will happily take a blood meal from deer, elk, and other large grazers and carnivores.
Know Thy Enemy and How to Destroy Them
These are true flies, and each has subfamily has many species within their general family – Tabanidae. While they share many similarities, they also differ from each other. A greater understanding of deer and horse fly helps people to decrease the populations of these terrifying pests.
They Bite for the Same Reason: The females both require a blood meal to complete their reproductive cycle. It only makes it worse to know that the blood they suck from you is helping them to reproduce and next year, there will be more females looking at you as though you are prime rib, and you are.
Similar in Appearance: Biting flies also have beautiful and brightly colored eyes. They are usually big, bulky flies that can reach to 1.25 inches in length. Horse flies often have dark bodies and darkly colored wings. Deer flies, which are often smaller have transparent wings dark lines or bands.
While they are similar looking, they do have differences. Deer fly, for example, has wings that are A-shaped whereas horse flies have wings that fold straight back when at rest. Horse flies also tend to be slightly larger with bigger eyes and a slightly wider body. Either will make you run for cover.
Their Mouthparts are Lethal: The female horse and deer fly have skills, and they use those skills to hunt and feed on their prey. Their drive to drink blood comes from their need to reproduce. As such, they are relentless in their quest to feed on warm-blooded mammals. People fear these obnoxious pests because of the razor sharp, dagger-like mouthparts which they plunge through your skin to sever the blood-rich capillaries. The evolution of both deer and horse fly created an efficient tool that turns flesh into a buffet of blood for large mammals. As painful as that sounds, it is not the bite that causes the most pain. That severe, sharp, stinging sensation is the result of the anticoagulant that they use to keep your blood flowing. The bite, itself is painful, but their saliva is worse.
They Both Spread Disease: During the biting process, both deer fly and horse fly can spread several types of disease such as anthrax, filarial worm, and equine infectious anemia. In an article produced by the University of Kentucky, entomologist Less Townsend estimates that each bit from a deer or horse fly removes about 1-cc of blood. To put that into perspective, the human body has about 5 liters of blood, which is equal to 50,000 cubic centimeters. Townsend estimates that a small terror cell of biting flies that number between 20-30 hungry females can extract a quart of blood in just ten days. That’s about 1/5 of the blood in your body.
In bad years, when there are lots of hungry female biting flies, their constant biting can negatively affect livestock. Farmers report decreased milk production, injuries, and disease thanks to biting flies.
They Are Hard to Control: Horse flies, deer flies, yellow flies, and green heads are difficult pests to control. Many are resistant to pesticides making chemical controls almost worthless. They also do not have many natural predators. So, they have free reign to terrorize people. Big spiders capture some of these driven females but not many. Plus, who wants to live with big spiders?
One method that works well is a special type of fly trap called the Fly Cage. Because deer and horse fly find prey in similar ways, the trap uses their tenacious habits to attract and then kill the females. Both deer fly and horse fly seek out large dark shapes that move. This is why deer, horses, cattle, goats, dogs, and humans make such easy prey. All are largish, slow moving, and dark. Big bodies present many opportunities to feed. Only man has limbs that present a danger to the flies. No matter, though, they will risk a swat to feed.
“Soft, pink, and such easy prey,” that is what Tabanus nigrovittatus — the greenhead fly would say about humans if they spoke. They do not speak but then they do not have to utter a word to get their “point” across.
Humans Make Great Prey
We greenheads and the other species of horse and deer flies really owe humans a huge debt. Humans not only provide an easy meal but also bring a variety of food sources to the table – so to speak. We don’t have to go hunt the exotic meal. No, ranchers pen them up so they make finding a blood meal easy — cattle, sheep, goats, dogs and the exotics like the llama, alpaca, and emu!
Humans are Very Entertaining
Come mid-June, it is nothing but fine dining and entertainment at the beach. You know they say, coconut oil is a new health trend and let’s just say that the Coppertone Brand of coconut oil sets off the taste of human blood like no other. One bite on a crowded beach and all the human’s stop and stare. By the second blood meal, people are gathering up their children, boomboxes, towels and headed for the parking lot. By the third bite, there is no more walking but a hurried jog and by the fourth bite, everyone is running. It’s the greatest. The trick is to wait until they are all unpacked and relaxed. It’s hard to wait that long but it is so worth the struggle.
Humans are Full of Irony
There are lots of ironies too. Humans have the brains, but not the smarts. They slather on all kinds of products that repel insects. Like those are going to work. Bah! We are not dainty mosquitoes. We are biting flies. We leave a mark. There is no question after we bite. You hear people say, “I think a mosquito just bit me.” There is no “thinking” when we bite. There is a pool of blood and an exclamation.
We love to hear that “slap” too as we are flying off. Ah, missed again. You can have another chance later when one of our sisters cuts you open with their scissor-like mouthparts and drinks your blood. Go ahead and spray on more Deet maybe light another citronella candle — dining should always be by candlelight.
While the parody of this story is somewhat comical, its basis is in the truth. Humans make great prey for greenheads and traditional repellents do not do much to thwart their biting. Another “point” for people to consider is that biting flies are not mosquitoes and what works to control mosquitoes will not work to control greenheads. To control greenheads people need to address the greenhead hunting strategy which is to look for:
- Large dark colored objects
- Meandering movements.
The best way to control greenheads and biting flies is use their own behavior against them. An effective tool for doing that is the Fly Cage. It attracts biting flies, such as the greenheads by presenting a large dark colored target and the subtle movement that biting flies zero in on. The greenheads fly in, but they don’t fly out and each female caught means that next year’s population of biting flies decreased by one or more broods. The Fly Cage is effective because it works to reduce the current population of biting flies and future generations too.
The beach – a perfect place to relax in the sun, enjoy the water, and spend a little family time. That is until the dog yelps, the kids start crying, and everyone starts running for the car. It feels like someone stabbed you with an ice pick and your wife is rummaging for the first aid kit. There is plenty of blood, but you’ are not shot or stabbed. You are suffering from the bite of a Green Head fly.
Ah the Beach
People see a wasp and they freak out trying to get away from it. Armatures! They have likely never felt those scissor-like mandibles of a green head slice open their flesh for a quick blood meal. Now that’s real pain.
The question is how do you get rid of biting flies at the beach?
Well you can douse yourself with deet or citronella but don’t fool yourself into complicity. The biting fly will hardly notice such defenses. These are visual hunters. They use those beautiful eyes to spot you as you stroll along the sand enjoying the surf. Insect repellent has little effect on biting flies. What you need is a Fly Cage – a fly trap that uses the biting fly’s own nature to trap it and ends its reign of terror.
Biting Flies and the Hunt
Horseflies and green heads hunt in a variety of ways. They are lurkers. They will land on a tree or bush and wait for something large to wander past them. They have compound eyes which means that they see well, but not crisp images like we do. They see shapes and have come to recognize movement and shape to mean prey.
Deer flies and biting flies prey on a long list of large creatures. They prey upon deer, horses, cattle, elk, humans and similar creatures. What do all those targets have in common? They are:
- Warm Blooded
- Emit Carbon dioxide
- No or little fur on their underbellies
- They often stop and graze or observe
Green heads have adapted to look for these traits when they hunt. At the beach, we stand out like a lighthouse in a storm. The green head is well equipped to track us too. They can sense the carbon dioxide that we breath. They follow that like a heat seeking missile follows a hot jet engine.
How to Get Rid of Biting Flies at the Beach
What the Fly Cage does is it uses the visual hunting part of these traits to lure in the green heads and then traps them. A Fly Cage is one of the most effective ways to rid the beach of green heads because it mimics their prey.
The good news for those of us who enjoy the beach is that we can do just that. We are not sure if it is safe to go in the water, but with a good fly trap on duty, the dry bits are a safe bet.
Biting flies are not only an annoying pest, they are down right painful. So how do we protect man’s best friend from the painful bite of deer and horse flies? We have been asking a similar question for generations – how do we protect ourselves from biting flies? The answers that we have come up with were not sufficient.
Getting Rid of Biting Flies like Green Heads
For a long while, we thought deer flies and horse flies were like mosquitoes because they breed in the same environment. So we used pesticides to poison them. We were wrong. Their life cycles are very different. Our use of pesticides did not affect the biting fly larva or the adults at all. We’ve tried tricks to keep them from pestering livestock and pets. Most of those tricks have failed.
Towards the end of each Spring and into the early part of summer, biting flies remind us of those failures. We go about our business only to feel the nasty bite of a fly that drinks our blood and flies away faster than we can swat it. It is the same with our livestock and with our dogs. They suffer and we suffer under those twin blades of pain. It seems hopeless. That is until lately. There is a new weapon that takes down biting flies. It is an effective way to rid our property of these painful pests. It is a fly trap that is smartly designed and deadly to biting flies. It does not use pesticides. It does not cause an environmental hardship. What it does is it draws them in and then trap them.
A Biting Fly Trap that Works
There are many fly traps on the market. Some of them are utterly useless. A few show promise. The Fly Cage is different. It takes into account the very nature of biting flies and that is why it is effective. Biting flies hunt primarily by sight. If you consider what they prey on, it is animals that are usually large, brown, and have thinly haired underbellies. The Fly Cage is a stationary trap that is large, mimics the look of a large animal and is movable.
Biting flies require moist soil. That is where they live when they are larvae. They live in the damp soil around rivers, swamps, and estuaries. When the larvae emerge as adults, they fly around in those areas looking for food. It is the females that bite because they need warm blood to complete their breeding cycle.
To effectively keep biting flies from pestering your dog, livestock or even yourself, you need an effective trap. It must take their habits and physical needs into consideration. That is exactly what the Fly Cage does. It tricks them into thinking that they have easy prey, but it is the biting fly that becomes the prey. The Fly Cage looks like a herd animal and has a black lure underneath it. That is what attracts biting flies to their underbelly. They hunt mostly by site and the Fly Cage fools them and then kills them.
If you want to protect your dog from the pestering and painful biting fly, you need an effective trap – the Fly Cage.
Biting flies are no laughing matter. Where are the biting flies in the winter? You might have noticed that those burning, stinging, bloody welt-inducing incidents have stopped. You might even breathe a big sigh of relief. So where do the biting flies go in winter? The simple answer is that they go to prepare for the next biting season. Let’s explore the lifecycle of these minuscule terrors.
The Many Forms of Insects
One key thing about insects is that they are not always in their adult form. Their life cycles are rather interesting in that they have evolved to deal with seasonal issues, such as cold winters, droughts, and even the scarcity of food.
The deer fly and horse fly are both dipterans — flies — and they have a complete lifecycle. They begin as an egg, hatch into larvae, form a pupa, and then emerge as an adult. The telling of where the biting flies go in winter is a story about their lifecycle.
Adult Deer Fly and Winter
The truth is that the adult deer fly species die when the weather turns cold. You might cheer at that thought or maybe raise your fist in triumph. However, by winter, the damage is already done. The female deer fly and horse fly both bite to ingest a blood meal. The entire purpose of that meal is to help them successfully produce eggs.
During their adult life, deer fly lay between 100-800 eggs. Every bite, every blood meal is a primer for another brood of eggs. Once the females have died off, their eggs are long hatched. The next population of deer fly secured. So as we raise our fist in triumph keep in mind it is the deer fly who has the last laugh.
Deer Flies and Overwintering
During the cold, winter months, the deer fly larvae are snugly enjoying a subterranean habitat. Once the eggs hatch, the larvae fall to the ground and burrow down into the soft, moist soil found around the margins of swamps, ponds, lakes, and wetlands. Here, they will burrow through the mud eating other insects, worms, and even each other. The earth is warm and the maggots enjoy an easy winter. Come the late spring, a portion of that population pupates and then emerges as adults. The laughter of man over the demise of last season’s adult deer flies becomes muddled curses emphasized by the slapping sound of a quick hand missing a clever predator.
You may feel that bit of laughter slide off your face as you read this but take heart. The key to eradicating deer flies and horse fly is to remove the adult females before they breed, bite, and lay that mass of eggs. The trick has a name — the Fly Cage. It is an effect means of attracting adult female deer flies and ending their reign of terror. The Fly Cage is effective against:
For every adult female biting fly the Fly Cage takes down, the next year’s population of predatory flies drops by 100-800. Now that is something over which you can rejoice.
Biting flies – deer flies and horse flies – belong in the family Tabanidae. They are members of the order Diptera. Dipteran is a true fly and as such many species are capable of spreading disease. Tabanidae is the family of beautifully colored flies with a nasty and painful bite. Painful in this case is a mild expression. The bite of a tabanidae is piercing as though someone has plunged a dull pair of rusty scissors into your arm and then forced them open. Once bitten by a horse fly or deer fly you become keenly aware of anything flying around in late spring through late fall. These are not small flies. In fact, horse flies can reach 25 mm in length. They are big, sturdy and agile flies that seem to hone in on you when you are least able to pay attention. They strike with the skill of a trained assassin, biting open your flesh and lapping up the blood before you can slap yourself so hard that it stings. Horse flies are excellent hunters and even the wariest of people fall prey to their chomping mouth parts. So how do biting flies find you? Let’s explore the prowess of these beautiful menaces.
Female Horse Flies Are Amazing Hunters
It is just the females that bite people. The males are plant sap suckers. The females, however, need blood from a warm-blooded creature to successfully reproduce. Horse flies and deer flies are such obnoxious pests that we have tried for decades and failed to eradicate them with pesticides. Yet, they are keen hunters. They use a variety of tools to find and target their prey and these are the things that allow them to find us with such ease. Here is a closer look at how they find us.
Horse flies have compound eyes. What that means is that they two eyes that consist of many individual lenses. They can see farther into the peripheral and a greater area than we can. However, they do not see clearly. What they see is a combination of bright and dark, shadow and shine. The targets of tabanidae are large mammals such as people, horses, cattle, deer, elk, and other animals with bulky bodies. Why is that? It is because, with compound eyes, they can see the shapes of larger animals easily. They track you by your movement. This is one of the reasons why they are so successful in hunting us. While sight is their main method of finding prey, it is not their only tool. Their antennae are adept at picking up chemtrails. More specifically, carbon dioxide which we exhale every time we breathe. Further, They can track us by our body heat which helps them distinguish us from darker surroundings. We cannot hide from them. They can find us by sight. They can find us by our carbon dioxide trail. They can find us because our body heat is within a specific range. This is why they are so successful.
It is how they hunt us that becomes their weakness. Pesticides do not work well on horse flies or deer flies. What does work are traps like the Fly Cage. The Fly Cage emulates the movement of large mammals. That movement draws the attention of deer flies and horse flies. They investigate their potential target but never return to breed, bite, or terrorize again.
The comparison of mosquitoes to greenheads is actually stark; however, there are similarities. Both are biting insects, but their bites are quite different. The bite from a mosquito is akin the bite of a small puppy. The bit of a greenhead is more like having your arm ripped off by a bull mastiff. It is the bite of both of these annoying insects that plague humankind. They are both diptera which means they are both flies. Their mouth parts are very different. Both pests use an anticoagulant to keep blood from clotting. That is what itches. The mosquito uses a needle-like stylet and gently pierce your skin. They drink your blood through what is essentially a straw. The greenheads use something akin to a pair of scissors. They rip open a wound, slicing through every vein and capillary in the process to create a pool of blood. So while they are the same, they are also quite different. Mosquitos predominantly prefer hunting at night and Greenheads during the day.
Controlling Greenheads and Mosquitoes
Mosquitoes spend part of their lifecycle as aquatic insects in shallow pools in salt marshes and bogs in wooded areas. Greenheads spend part of their lifecycle burrowing through the moist, rich soil of salt marshes. This is a primary reason why mosquito abatement programs do not affect greenhead and other horseflies. Mosquito abatement treats standing water. The horsefly reproductive cycle, including that of the brutal greenhead, takes place in a very different environment even though it is in the same neighborhood. This is one of the reasons that it is so difficult to treat horsefly populations. In fact, humanity has tried and failed to kill off greenheads with pesticides. Horseflies are rugged tanks with wings that insecticides are not very effective in controlling. How then do you control greenheads if you cannot use pesticides? The only real option is an ingenious invention called the fly cage. As a tool, it mimics some of the things that attract greenheads to their victims. It is large, dark colored, and has a bit of movement to it. The process is mechanical rather than chemical. Horseflies and greenheads swoop in for a blood meal and never return.
How Are Mosquitoes and Greenheads Alike?
Oddly, for as different as the two pests are, they share a similarity. The females of both species do the biting. When they are ready to lay eggs, both the female mosquito and the female horsefly need red blood. The protein in the blood helps in their reproductive process. Both species of females seek out humans, horses, sheep, goats, and other large animals on which to feed. Without that blood meal, neither insect can successfully reproduce. That is another reason why the Fly Cage is so successful. It mimics the victims of greenheads.
If you were counting on mosquito abatement to help rid your place of greenheads, you will be “sorely” disappointed – pun intended. We all know how painful greenhead season is to anything that stands still for half a second. There is help available.
Ah, the joy of summer. The sound of children playing. The drone of insects. The slapping sounds as the greenheads invade. For those of you who know the greenhead fly here are five facts that might keep you indoors this summer.
1. Greenheads — These Flies are Violent Eaters
Unfortunately for large mammals such as horses, cattle, barnyard animals, and humans, greenheads enjoy eating our blood. They are highly efficient at getting a blood meal too. These are flies that do not enjoy a leisurely meal. They swoop in, make you bleed, eat your blood and fly off before your hand can react to their presence. It is that efficiency in hunting and eating that makes their attack and bite so painful. They need to get to your blood fast so that they have time to gulp it up and be gone before you smash them. To that end, it is the design of their mouth that makes them such a menace and such efficient pests.
Their mouth parts include two sharp tools that look much like a pair of scissors. They jam those mandibles straight into your flesh. Then flex outwards severing every capillary and vein with which they come into contact. They use a salivary pump to douse the wound with an anticoagulant chemical. Then they use a syringe-like device that in their mouth to start sucking up your blood. All this happens in a split second. Then they are flying away full of your blood.
2. It is their Saliva that Hurts
Not only do they punch a large hole in you, they gush in an antiseptic-saliva that stimulates blood flow. It burns and causes your nerves to respond with pain.
3. It Is Your Blood That Keeps the Greenhead Population Alive
The female greenhead needs blood to finish the reproductive process. They do not just lay a single batch of eggs; they lay a continual batch of eggs. Every time they drink your blood they receive enough protein to produce a couple of hundred more eggs. So one female greenhead can unleash a summer of torture. Imagine what a whole colony of female greenheads can do.
4. Greenheads are Big
Greenhead flies are big horseflies. They reach over a half of an inch in length. Most horsefly species range from .25 inches to well over 1.5 inches in length. These flies are so big that insect repellant does not bother them.
5. Get ready Scream! Greenhead flies are fairly resistant to pesticides.
People have tried for decades to poison greenhead flies. The flies for the most part just laugh at you. Humans have not done a good job of eradicating Greenhead flies. This is mostly true because we did not understand them well. Those poor attempts at poisoning them resulted in a few deaths. We killed off the weaker flies and what remains are the ones that have a resistance to pesticides. If you want to get rid of greenhead flies, then try the Fly Cage. It is a trap that works on many levels. Two of those are the Greenhead’s natural instinct for dark colors, movement and the fact that they target large animals. The result, which is not toxic, is that the greenheads fly in and never fly out. The Fly Cage is the greenest solution for an insect that insecticides can’t kill.