For most of the year you may not have to deal with horseflies. Most of the time, you will not get any disturbance from horseflies. They mostly have nectar as their food and assist in plant pollination. However, you begin to notice their vampire tendencies when it is time for them to breed.
They begin to search for blood and just as with mosquitoes, a female horse fly requires blood in order to successfully lay eggs which may number between 25 and 1000. For most locations in the United States there are horse fly seasons, early part of summer.
They mostly carry out their attacks as a group. You might be wondering what got them attracted to your environment in the first place. Understanding what leads them to attack can help you implement control measures successfully.
The Basics
The length of a horse fly can be anywhere between 3/4 and 1 inches. They have large heads as well as large eyes. They also have wings that might either be clear or dark. They make use of mouthparts that are sharp as razors to pierce the skins of mammals from which they draw blood from the inflicted injury. They are very similar to deer flies but happen to be bigger. Horse flies are responsible for the spread of diseases which include anaplasmosis, Lyme disease, anthrax, as well as, hog cholera, filariasis, tularemia, and more.
Weather
You mostly find a rise in horse fly attacks during the summer season. This is a time when you have more sunny days without so much breeze. They are mostly attracted to areas that are warm and sunny but steer clear of dark areas as well as areas where there is a lot of shade. They only feed during the day and not at night. A drop in temperature will lead to a reduction in horse fly attacks. Their activity is most significant in August because this is the time that they get to breed. You will also likely experience them between June and July.
Read More About Horse Flies
https://entomology.ca.uky.edu/ef511
Moisture
Horse flies larvae require moist wet muddy areas to develop, so any time you can alter these areas of development will be a reduction in populations. Make sure to use appropriate products when applying near water. Eliminate excessive wet organic matter around barns and pastures.
What are they attracted to?
You will mostly find horseflies around swimming pools, edges of ponds, excessive moisture, muddy stream areas. For swimming pools. the horse fly is is attracted by the shiny surfaces as well as movement of swimmers. Swimming pool water is also dark and warm with the presence of carbon dioxide. The fact that they are visual in nature means that a horse fly will consider moving towards water surfaces that are shiny attractive.
They are attracted to large moving objects, such as horses, humans, and prefer dark objects.
Controlling Horse fly attacks
Most people believe that horseflies cannot be controlled. However, you can implement some fly control horses measures that will ensure that these insects do not bite you or your horses. You can make use of horse fly repellents and horse fly spray. You may also consider wearing clothing which has a bright color together with a protective repellent spray so that you do not attract horseflies. If you have horses that graze, ensure that they stay indoors during the daytime but let them out to graze when it is nighttime. This is because horse flies usually attack during the day but not at night. Also, consider making use of other horse fly control products.