The Confusion of Cockroach Gel selection

The Australian Professional Pest Control Market is spoilt for choice when it comes to cockroach gels.

cockroach - Bayer - Pest Control

The Australian Professional Pest Control Market is spoilt for choice when it comes to cockroach gels. There are a broad selection of toxicants, matrices and colours. But have you ever considered why? How do you cut through the product ‘claims’ and look for the right attributes in a gel to suit a given situation. Let’s take a look at a number of common use patterns and set some ‘must haves’ when we are evaluating the options out there.

The Australian cockroach gel market is comprised of a number of broad use categories. These are determined by where the gel is to be used (eg domestic/commercial) and what for (clean-out/maintenance).

Maintenance Cockroach Gels:  consist of products that are placed most often in commercial accounts and are responsible for controlling cockroach populations which are low to moderate. Put another way we are seeking to control developing populations. Most often maintenance gels are used after a knock-down or clean-out gel program has rapidly reduced cockroach populations to manageable levels. Maintenance gels are applied more frequently and for longer periods than premium gels. These are the gels we use day in day out to ‘maintain’ our program and in commercial accounts, the gel we use the most. Therefore they are preferably lower in cost per tube than premium gels.  Finally the other desirable feature of these gels is that they are a useful rotational partner with other gels in our program particularly to prevent chemical resistance.  

Domestic Cockroach Gels: Domestic gels are mostly used on a 12 month service interval. The number one feature of such gels is that they remain effective (attractive) on surfaces for long periods of time. A good choice here is a sustained level of attractancy as opposed to high attractancy over a short period of time. toxicants used in these products should be moderate to fast to ensure control of resident populations but need not be capable of the rapid reduction of large numbers of cockroaches as often found in commercial accounts. 

What about white versus brown cockroach gels. Which are better?

This is something that I get commonly asked and for me it doesn’t really matter. Many users of white gels choose them for domestic purposes because the gel placements are disguised in white melamine cupboards. This may be true but careful placement can overcome the obvious contrast of a brown gel on white surfaces. The colour of a gel is due to the combination of its food components and not due to the addition of colouring agents. However if colour is important to you, then ensure the gel of choice does the job it is intended to.

Cleanout/Premium Cockroach gels: Finally we have the cleanout/premium gel category. Gels in this group are often categorised by premium toxicants and attractive bait matrices resulting in rapid reduction in cockroach populations.

How fast? Typically, lab trials of these products will show 90+% control of cockroaches between 12 and 24 hours. This will translate into a noticeable reduction in the ‘field’ within 24 hours somewhere around 70+%.

Gels in this category need to be highly attractive so that their premium toxicant can do its job in the shortest period of time.

So let’s summarise what we need to look for:

Gel Category

Speed of Control

Gel placement attractiveness on surface

Cockroach population at time of application

Maintenance

Slow to moderate

Important but replaced monthly during service

Low to moderate

Domestic

Moderate to fast

At least moderately over a long period

Low to moderate

Premium/Knockdown

Fast (<24 hours)

Critical (initially)

Moderate to High

Further advice:

To kill cockroaches more effectively remember:

  • More small placements are better than large point sources
  • Think about cockroach behaviour and place your gel in locations they are likely to come into contact with foraging cockroaches such as cracks, crevices and corners and junctions of cupboards.
  • Care for your gels and baits:
  1. Gels contain food ingredients and whilst stabilised do not like direct sunlight. Sunlight breaks down the matrix and the toxicant. Extreme exposure may result in gel bait separation, poor attractiveness or activity.
  2. Minimise heat as much as practical. Don’t carry more gel in the vehicle than you think you’ll need.
  3. Avoid contamination by other products in the vehicle. Preferably store in a dedicated bait storage compartment, bag or box
  4. Use a gel with the best combination attributes for the job you are treating. Don’t use a maintenance gel when really a cleanout gel is needed. Conversely, don’t waste money using a premium gel when the job calls for a maintenance gel to ‘manage’ low cockroach numbers.

Try and categorise your current choice of product. Are you using it as it was designed?