Frequently asked questions about H-traps

When should I set up the H-trap?

Depending on the temperature, horseflies will emerge from early spring (which in Europe is from April onwards). The female horse fly will then immediately start looking for blood to assist in production of the next batch of eggs. It is important that the H-trap is in position before this starts happening in order to have the maximum catching opportunity, especially to help reduce horse fly numbers for subsequent years.

Where should I install the H-trap?

The H-trap needs to be installed in the vicinity of horses or other livestock. Horseflies can see the infrared radiation coming from horses over a long distance. If a choice has to be made, horseflies will prefer to travel to a large group of potential victims (horses), rather than going to one isolated victim (the H-trap).

When should I break down the H-trap?

At the end of the season, typically late autumn, horse fly numbers will start to dwindle, caused by colder temperatures and age. By this time we recommend that the H-trap is broken down, cleaned and stored indoors ready for use again next year.

Can the trap be used indoors?

The H-trap will have no effect indoors. In order to function, the trap needs the sun and natural solar radiation to create a temperature difference between the surroundings and the black ball. Indoors the black ball will not be heat up and no temperature difference will be created and horseflies will not be able to see the H-trap.

What is the maximum effective coverage for the H-trap?

When the H-trap is used to control horseflies near to horses we recommend to place one H-trap with a maximum of 5 horses. Horseflies cannot see the difference between the H-trap and a horse. With a maximum of 5 horses there are better chances to catch the flies in the trap and therefore build up a good control curve over time.

Is the H-trap weather proof?

The H-trap is weather proof and storm proof. Needless to say, it will not withstand extreme weather and wind conditions, such as a hurricane. In these situations may be advisable to remove the ball and funnel temporarily.

Does the H-trap attract all insect species?

The functionality of the design is that the trap will only attract those insects that are drawn to heat and infrared temperature (most flying insects can see ultraviolet light, not infrared light). These insects, typically blood sucking insects, will be attracted by the H-trap. Field tests (see separate downloadable documents) have shown that other insects may be caught and this is influenced by the surrounding crop and environments. Much of the trap capture will be incidental. The green colour of the funnel hood is designed to reduce the risk of catching bees.

Does the H-trap need maintenance?

In order to aid fly capture, it is recommended that the collection bin is filled with soapy water. A periodic emptying of the collection bin is recommended once every 1-2 weeks, depending on insect catch. Once a month, check if the ball needs an additional inflation. It is recommended therefore that the hand pump is kept where it can be retrieved easily.

Are spare parts available?

Yes. Contact Sentomol to obtain any parts which you need to re-order.