Here’s the best way to choose, to use and to place insect light traps.
Editor’s Note: This article was adapted from Techletter, a biweekly publication from Pinto & Associates, Mechanicsville, Md. To subscribe, visit www.techletter.com or call 301/884-3020.
Insect light traps (ILTs) come in many types, shapes and sizes. In a food facility like a restaurant, grocery store or food warehouse, your problem is to decide which models to install and where to put them for best effect.
Choosing Trap Type.
Whether you call them ILTs or EFKs (electric fly killers), they all use ultraviolet (black light) to attract flies and other nuisance flying insects. They differ, however, in how the insects are trapped or killed. There are two main types.
Sticky board traps trap insects on a sticky surface. Some use an electronic pulse to stun the insect, causing it to fall onto the sticky board. Others are passive traps where the insect happens to land on the glueboard. The main advantage to these traps is that insects are held whole on the sticky board with no scattered fragments that may contaminate surfaces. They are usually the preferred trap in food areas although they should not be installed above food surfaces. A disadvantage is the limited capacity of the sticky board, requiring more frequent servicing. This is most suitable for accounts with lower pest levels.
Electrocuting traps produce a high-voltage, low-amperage arc to electrocute insects that fly through the grids to the light and then hold them in a catch tray. These traps are most suitable for accounts with higher pest levels since they need less frequent servicing.
Where to Place ILTs.
The first principle of light trap placement is to intercept flying insects before they enter critical areas of the facility. If they have already invaded the facility, you want to place traps to draw them away from food and customer areas and towards the traps (see graphic above). A careful inspection is needed to determine where flies and other flying insects are entering the account and where they are resting once inside. Study the flow of people and products through the facility; flying insects follow these same pathways.
Narrow hallways are a good installation site. In general, ILTs to capture flies are placed low, only a few feet from the ground. This is where flies are most active during the day. Traps placed low are also less likely to scatter fly parts and (as a bonus), traps placed low are easier to service. The exception is ILTs used to intercept moths and night-flying insects. These should be placed high where moths fly. Place traps where there is little competition from sunlight or ambient light, but where there is low air movement. Don’t place ILTs in direct sight from doors or windows.
Five Tips for Granular Fly Bait
One fly control method that is often overlooked by pest management professionals is the use of granular fly baits. However, these baits can provide effective fly control as part of an IPM or Insect Resistance Management program. Here are five tips to keep in mind when using a granular fly bait:
- Apply fly bait at the labeled rate. Don’t overfill bait stations, as flies will only feed on the top layer of bait in the tray. Overfilling a bait station will only result in wasted bait.
- Rotate between fly baits with different active ingredients. Because there are large numbers of flies per generation, they can quickly develop either resistance to a single active ingredient or aversion to a specific bait matrix. It is recommended to rotate between two to three fly bait products with different active ingredients each year.
- Apply fly bait in warm, motionless areas. Flies prefer these types of sites for resting and feeding, so bait will be less effective in cool or breezy locations.
- Don’t apply fly bait to moist breeding areas. Fly baits are designed to be placed on dry surfaces for control of adult flies, not for control of the larvae that develop in moist environments.
- Don’t wait until fly numbers are large to apply fly bait. Apply fly bait early in the season to help keep fly populations low.
Although chemical controls are seldom used as the primary method for controlling filth flies, these tips for granular fly baits can supplement other control efforts to help keep your customers’ properties free from the nuisance of these pests. — Dr. ElRay Roper, Senior Technical Representative, Syngenta Professional Pest Management
The authors are well-known industry consultants and co-owners of Pinto & Associates.