The following article was written by Mike Stringham, Extension Entomologist at NC State University. Mike works extensively with poultry operations and is considered an expert on darking beetle control.

Summer is here, and as bad as the darkling beetle infestation may seem in your poultry houses right now, it’s a safe bet that their numbers will go through the roof once the weather really warms up. Here are a few things to think about that may help reduce costs and improve control of this common poultry pest.

Use the most effective and economical method of application. Dusts are easy to apply and coverage looks impressive when a cloud of dust fills a building from floor to ceiling, but there may be more flash than bang for the buck here. First, dust applications just don’t penetrate as well as sprays into the cracks and crevices where beetles hide. Secondly, dust treatments may actually cost more. A dust product that costs half as much as a liquid concentrate sounds like a good deal. Right? Not necessarily. Dusts generally contain less active ingredient than spray concentrates. Even without the cost of extra labor needed for a spray treatment, dusts can still be more expensive if you must apply four times as much product to get the same concentration of active ingredient per unit of surface area.

Timing of application is also important. Many beetles and beetle larvae are just below the surface of the litter right after birds are removed from the house. A treatment made immediately after load out will kill a higher percentage of beetles than if you wait a week or more to treat. Where beetle infestations are extremely bad, treat just after load out and again just before birds are placed back. Finally, consider skipping treatments in late summer or early fall. I know the idea sounds crazy since beetle infestations are often heaviest at that time, but there is a good reason for doing it. Beetle numbers will fall naturally as soon as cold weather hits. Why not let the weather knock down the beetle population for you and save a little on your treatment costs. Start back with regular treatments in mid winter to drive the beetle population as low as possible before the weather warms up in the spring. This may delay the onset of severe beetle infestations by a month or two in the spring and summer.

Target treatments effectively. Poorer than expected beetle control is due in part to the fact that the application rates for the available insecticides are based on surface area. Effective control, then, depends on most beetles and larvae being in contact with the treated surface. That would be fine except for the fact that litter is a volume – a three dimensional space made up of a given width, length and depth. Most beetles won’t come to the top of the litter, especially since insecticides are often repellent and tend to drive the beetles away from the treated surface. With 4 to 6 inches of old litter below the treatment zone, there’s plenty of untreated space beetles can escape to.