Carpenter ants

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Jan Pijpelink

Minister of Fire
Jan 2, 2015
1,990
South Jersey
We see carpenter ants on the 2nd floor of our house (raised ranch). Not on the lower floor. How do I get rid of them without using too harsh chemicals?
 
Its likely they have nest somewhere in the house. Sometimes the nest is located in an area of wet rotten wood, other times its located in some other location. Fascia boards behind gutters is popular spot.
There is bait product in a syringe that has worked well for me https://www.seedworldusa.com/produc...MIm5fLluWj2gIVhR9pCh0yrgwkEAYYBCABEgIYmvD_BwE

The ants carry the bait back to the nest and then it kills the nest. I have tried the granules in the past and was far less successful. I dont like the granules as you are supposed to cover a "zone of death" around the home so the pet and ground exposure is high. The gel is applied in small quantities where the ants are present. I think its a "sweet bait" so you would need to keep it clear where a pet might try to lap it up or you need to get it down in crevice that is out of the weather. I put mine under a door sill. Psychologically you dont get much for $20 buck but it was far more effective than the granules for me.

Some folks advocate a home brew of boric acid and sugar but I have tried it a few times and never had any luck.

I had an earlier infestation under a front door sill where the builder didnt detail it right so I had some rot. I rarely saw ants there but saw plenty of them 20 feet away. Once I replaced the door and part of the sill, I dont see them. They also will tunnel and nest in foam insulation. I have 1" of foam on the exterior of my house and they tunneled up through it from ground level up under the clapboards. They are quite careful not to tunnel through the surface but the underlying foam was swiss cheese.

The annoying thing with carpenter ants is where they are swarming may not be that close to the nest. I had a nest in between my second floor and 1st floor several feet away from the outside walls. When I had an outside wall open during re insulating, I found a very distinct ant highway from under the outside clapboards through a gap in the plywood and then up the wall to the top plate and then presumably across the top of the ceiling to the nest.
 
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borax and sugar solution--same thing in some Terro products, is pretty safe. Isn't exactly good to eat, but pretty reasonable compared to some pesticides.
 
Its likely they have nest somewhere in the house. Sometimes the nest is located in an area of wet rotten wood, other times its located in some other location. Fascia boards behind gutters is popular spot.
There is bait product in a syringe that has worked well for me https://www.seedworldusa.com/produc...MIm5fLluWj2gIVhR9pCh0yrgwkEAYYBCABEgIYmvD_BwE

The ants carry the bait back to the nest and then it kills the nest. I have tried the granules in the past and was far less successful. I dont like the granules as you are supposed to cover a "zone of death" around the home so the pet and ground exposure is high. The gel is applied in small quantities where the ants are present. I think its a "sweet bait" so you would need to keep it clear where a pet might try to lap it up or you need to get it down in crevice that is out of the weather. I put mine under a door sill. Psychologically you dont get much for $20 buck but it was far more effective than the granules for me.

Some folks advocate a home brew of boric acid and sugar but I have tried it a few times and never had any luck.

I had an earlier infestation under a front door sill where the builder didnt detail it right so I had some rot. I rarely saw ants there but saw plenty of them 20 feet away. Once I replaced the door and part of the sill, I dont see them. They also will tunnel and nest in foam insulation. I have 1" of foam on the exterior of my house and they tunneled up through it from ground level up under the clapboards. They are quite careful not to tunnel through the surface but the underlying foam was swiss cheese.

The annoying thing with carpenter ants is where they are swarming may not be that close to the nest. I had a nest in between my second floor and 1st floor several feet away from the outside walls. When I had an outside wall open during re insulating, I found a very distinct ant highway from under the outside clapboards through a gap in the plywood and then up the wall to the top plate and then presumably across the top of the ceiling to the nest.

It's a sweet bait. The active ingredient for maxforce is fipronil, which is a very popular flea medication. If you've pet a cat or dog since the 90s, you've likely been exposed to it. That said, apply it to where you're seeing the ants. Expect them to tell their buddies and swarm it.

Depending on what the colony is looking for at the moment, they may not go for maxforce. I would recommend Advion then.

In NY, you have to be licensed to buy these products. Other stares vary on their laws. Read the instructions. It is a neurotoxin.
 
Oh, and locate that water leak in your house. Just because the ants go away, the rotting wood doesnt.
 
Oh, and locate that water leak in your house. Just because the ants go away, the rotting wood doesnt.
I can confirm this. I had a carpenter ant issue because I had a rotting wood issue. In my case, the flashing was done incorrectly. The way I found it is by inspecting under the siding where the siding ends and cement foundation begins. The OSB wood was rotting away in a few places. Ripped all the siding off that area and found a couple hundred ants tucked away for the Fall.

Carpenter ants come out and hunt at night. When the weather gets warmer, you will see them making trails out of the house. Make sure you bait those trails.