“Hi Ion, I have a question about termites in the garden, in old sleepers. My question is, can I spray around the area with Bifenthrin to kill them off?” – Ken.
Ion: Yes and no.
Retaining Walls Two Types of Termites
There are two types of termites that are often found in retaining walls and build sleepers used to build retaining walls. One of them is a plastering type of termite, which also, are a minor pest. And it makes a very, very thin fragile covering over a fair amount of the sleepers that are showing.
And, yes, that might be brushed off and the area could be sprayed. So, and then that would probably kill off that colony because it probably doesn’t have a very big nest. And there are pictures of that in our ‘how-to’ guide of that type of termite.
They also are found quite often on fences. And, again, there’s a massive thin sheet of mud over the fence. And then, that can be sprayed. But the other termite which gets in behind retaining walls is the either of the two serious ones, the Coptos or the Stilos. And they would use the retaining walls for the very first male and female when they have a colonizing flight, and they can get in behind that retaining wall, and they’ve got soil, and they’ve got food, and they’ve got some protection from birds and lizards, and so they get going.
And so, if those sort of termites is in the retaining wall – sorry, let me start again. If there are termites that have not been putting a big shooting of mud over the outside, like, you see mud in the crevices, in the gaps between the sleepers, then there are two options here – you can fix a termite bait over the holes or into the sleepers, so they’re directly biting into the sleepers.
Kill Termites by Termite Traps
Or, you can put Termite Traps above the sleepers on the ground above the sleepers. Either way, the scouts looking for the food are likely to find the traps, and then it’s very easy to add bait to the top of the traps, to control the colony that’s hiding it behind the retaining wall.