Controlling cockroaches is skilled work, requiring a thorough IPM approach and a suite of products suited to the job.
Cockroaches are an ancient group of animals and have been around for over 350 million years. You don’t survive that long without a great survival instinct. One of the keys to success is their ability to adapt to different environments. Everywhere that man has colonised, so too has the cockroach – even the depths of space are not off limit!
To tackle and succeed with a cockroach control program you need to have a strategy not just a treatment. Your decision on which methods to use should be flexible but should be based on an integrated pest management (IPM) strategy involving:
- Thorough inspection – cockroaches are cryptic
- Identification of your pest – tells you where they will be found
- Predictions of current and future problems – will my treatment be compromised?
- Evaluation of all factors – what is the best approach?
- Implementation – put the plan into action.
Always pay attention to the environmental conditions that support or enhance the infestation and adjust these conditions if possible. Important examples include reducing moisture, food sources or harbourages.
Different control methods
The perfect cockroach treatment requires the use of different product types depending on the site of application:
- Sensitive areas such as food areas, electrical appliances, computers, etc, require the use of baits (such as Maxforce Original, Maxforce Gold and Maxforce Fusion)
- For harbourages such as ceilings, wall voids, electrical cabling and other cracks and crevices use dusts (Coopex Dust)
- Crawl spaces, entry points, garbage areas or other areas where cockroaches will frequent on their incessant wanderings are best tackled by an effective residual space spray, such as Temprid 75.
Bayer recommends taking the complete ‘tool box’ at your disposal to the treatment (baits, dusts and sprays). Which products you decide to use will depend on the situation – certain situations may require using more or less of one product type.
Which spray should I use?
The type of spray formulation that is best for cockroach control depends on the surfaces to which it is being applied. When dealing with cockroaches, you will encounter the full range of surfaces from highly porous to highly non-porous and everything in between. For maximum effect you need the application of active ingredients to be lightly and evenly distributed across the surfaces. As the cockroach moves across the surface, small crystals of active ingredient stick to the antennae and body segments. The cockroach cleans its antennae methodically so the active is ingested and fatality ensues.
The best formulation type for depositing the active ingredient on the surface is a suspension concentrate (SC), followed closely by wettable powders (WP). When using emulsifiable concentrates (EC), the active ingredients will be absorbed into the porous surface making them less available for uptake by the insect.
SC formulations have many other advantages such as ease of mixing, great tank stability, low visual deposits and they have very little odour due to the absence of solvents. However, you must agitate suspension concentrates; firstly in the bottle before you decant your measured volume for a tank mix and secondly at least every five minutes when they are in your tank. If you do not agitate then your delivery of active will not be consistent and your results will be very erratic.
Bayer’s recommendation for a surface spray for large cockroaches is Cislin 25, which contains the powerful active ingredient, deltamethrin. This active is over 1000 times more potent than the older spray products such as Baygon. If your target pest is the German cockroach then the use of deltamethrin alone will not be sufficient.
Bayer’s recommendation for a surface spray against German cockroaches is either Crackdown (containing deltamethrin enhanced by PBO plus d-tetramethrin) or Temprid 75 with the dual actives of imidacloprid and beta-cyfluthrin. Bayer claims the activity of imidacloprid amplifies the potency of the beta-cyfluthrin making Temprid 75 an outstanding killer of this difficult pest.
For added confidence in your treatment consider combining an insect growth regulator (IGR) to your adulticide spray, for extra activity against the juvenile forms. Bayer has an IGR, Starycide, which is a chitin synthesis inhibitor that kills cockroaches as they moult from one instar to the next.
This product has an exceptionally long life span and goes to work for you in the background, killing emerged nymphs and juvenile stages long after your surface spray has lost its effectiveness.
Don’t forget the inspection
The most important piece of equipment in cockroach management is a good torch and you should always carry a small mirror to help you identify infested crevices. A complete inspection before and after treatment is vital to ensure all hiding places are treated and control has been achieved.