2 replies to this topic

[Ameise]

Hey there.

 

My wife and I bought this house last September, and since then, I've been dealing with issues in the yard - it seems the previous owners were very poor on lawn, yard, and tree maintenance. While examining the yard, I basically only found the following:

 

• A *lot* of Tetramorium sp. cæspitum. Almost all ants in the yard are these.
• Some small garden ants, but not many, and I haven't found a colony.
• A few roaming Tapinoma sessile queens. No colony found.
• A few roaming Camponotus pennsylvanicus workers - major and minor. I've found no colony on my property, or evidence of any. I suspect they're from neighbors.
• Some grey Formica. I have not found any colonies of them, I suspect they're from neighbors.
• Some red Formica. I've found one colony of them, and it's very small. The rest are probably from neighbors.
• Some Solenopsis molesta colonies. Hard to find, I suspect there's more. They don't seem to really compete with any other species, though.

The Tetramorium, as they are in my yard, are fairly pestiferous and aggressive. They make tons of nests, mess up pavers, and in general seem to be preventing other species from taking hold. Terro bait doesn't seem to harm them - one even made a branch nest inside the container!

 

I'm unsure what to do. I've been considering:
 

• Bringing some logs or wood to the yard in the garden areas to encourage Camponotus (the most common around here is pennsylvanicus, though I suspect novaboreacensis and nearcticus are in the area as well), though I'm wary of this as they may try to make satellite nests in the house and become pestiferous.
• Bringing some queens of, say Prenolepis imparis to the yard and encouraging their growth. The species is very common around here, but not in this neighborhood for some reason.
• Something else?
• Find some way to kill excess Tetramorium colonies. There's simply too many, and they've basically occupied the lot and kill anything else that tries to move in.

 

I suspect that there have been too many lawn treatments and other things going on in this neighborhood and its somewhat sterilized the ground. I grew up 20 miles north of here, and the variety of insects was much larger, and I'd never seen so many earwigs. They're everywhere.

 

Any thoughts on what I should do?

[Cameron C. Thomas]

You have quite the endeavor on your hands! I will try not to be too much of a downer.

 

Unless you have a few acres and are outside of suburbia, there isn't *much* you can do, unfortunately. For example, I have an ~8000 sq. ft. lot in suburban Vancouver ripe with Tetramorium and Tapinoma, and there really isn't anything I can do about that. These ants go where the people go, and even if you were able to selectively remove them from your yard, they'll be back next year from other yards in the neighborhood. Established Tetramorium colonies will prevent other species from coming in, especially if you have a smaller yard and the colonies are dense, and both of these genera grow like crazy.

 

For encouraging more diversity, you'll want your yard to be as close to your naturally occurring local ecosystem as possible. This means planting native grasses, locally occurring sources of extrafloral nectar, and generally letting the system do its thing. Scatter some larger logs throughout the yard to encourage Camponotus. Other species may take up residence under the bark and under large stones if placed throughout the yard. This will encourage insect abundance and diversity, which will also increase ant abundance and diversity. Again, there is the issue of scale. If you have a small yard and live in the suburbs, this will only be so effective. It works much better if you have plenty of land. The other issue you will likely run into is your neighbors, who may not be happy with your new *natural* landscape.

 

Best of luck to you! 

Edited by Cameron C. Thomas, June 18 2017 - 2:22 PM.

[cpman]

You can try selectively poisoning the Tetramorium. It's worked to some extent for me with fighting S. invicta. You need to be careful not to kill the other ants. Boiling water on the nests of the Tetramorium could potentially kill them if you don't want to work with pesticide -- and will pretty much harm only them. It may take a couple treatments though.

The tough part is simply that established colonies will kill any newly introduced queens -- especially Tetramorium. I also imagine that they produce many, many queens that rapidly fill in any appropriate habitat. So you may need to kill Tetramorium queens when you see them. For S. invicta, this is just me crushing any I see to prevent new nests as much as I can. It's not entirely successful and is pretty tedious, but it can help.

I'm also helped by the fact that my neighborhood has never been that badly filled by RIFA.

I don't know how effective these measures will be in somewhere with such a big infestation.

So, you need to somehow get rid of them in addition to providing appropriate habitat for native ants.

Edited by cpman, June 26 2017 - 2:08 PM.