Why would ants cover Terro with dirt?

Old 07-10-16, 07:38 PM
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Why would ants cover Terro with dirt?

Why would ants cover drops of Terro with dirt? Terro has worked well for me before, but there's a colony of ants invading my garage that aren't that interested in the bait. If I put a drop or two of Terro on the floor, they will sometimes collect it. But other times they will cover the drops with bits of dirt. What are they doing?

By the way, these ants seem immune to Ortho Home Defense (bifenthrin & zeta-cypermethrin) unless sprayed directly on them. As soon as it dries, they just resume their trail over it (I've been at this for over a week now). On the other hand, vinegar Windex killed the ones I sprayed and they seem to be avoiding the area now. I just hope the spraying didn't encourage them to move farther into my house because I know they are in the wall.
Old 07-11-16, 06:11 AM
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First thing I would try and do is ID the type of ant's your trying to deal with.
No clue why there covering it up like that.
I once saw where rat's had covered a 12" X 12" glue trap with insulation so they could walk over it without getting stuck, there smarter then we think.
Old 07-11-16, 07:08 AM
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Pavement ants, I think

I haven't looked at one up close to identify for sure, but I think they are pavement ants.
Old 07-11-16, 07:51 AM
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Hi rich. I had to look up "pavement ants", they are little buggers if I found the right ones.
They are sweet eating ants and should be easy to bait. Covering the Terro is funny but does not mean they aren't taking some back to the colony.

I have to deal with carpenter ants which are much larger and difficult to bait, sometimes they take it sometimes they don't. I do have a picture of several ants around a few drops of Terro feeding like pigs at a trough.

But, to my point. When I can catch an ant inside I put them in a bottle with some Terro. I shake the bottle gently to get them well coated and then release them. I try to put them outside IF I can identify some paths I feel are from the same group but otherwise i put them back where I found them. now, some die before they make it back to the colony, but if I leave them there they disappear. Others collect them and thus the same results, the Terro goes back into their food chain.

In your case those little fellows may have difficulty with the sticky Terro. I just tested mine and it appears to be water soluble so you could try a very small ratio of water to a few drops of Terro. You still want it to be sticky but something they can escape from.

Bottom line is within a week they all suddenly disappear.

It may take some trial and error, but contaminating them directly almost guarantees the poison will get back to the colony.

For my long term solution I am slowly eliminating their access, difficult but working.

Old 07-11-16, 08:51 AM
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Ants like to live in the ground as well as other places. The dirt/soil that we see is the excavated dirt from their new/expanding nest under ground. Itís possible they may be covering the bait as a defensive reaction but more likely itís simply coincidence as you placed the trap where you see the ant activity.

They still may be taking the bait back to the ground nest but another likely scenario is that the previous sprays have rendered the bait unpalatable to them. The residual sprays that you used work quickly when sprayed on them directly but work slowly after it dries. Vinegar is simply a repellent when it dries, but will kill on contact due to the acetic acid.

Two things to try:

1) Try the gel baits that come in the plastic syringes. The gels are usually protein based. Ants dietary needs change through the year between carbs and proteins. Terro is very effective, as long as it isnít contaminated even slightly on or around the station, but is ineffective if they are in protein feeding phase.

2) Use the bifen/zeta in a compressed air sprayer (pump sprayer) as a pin stream and find gaps/cracks/crevices that will accept the insecticide so that it runs down into and below the slab. When you find those gaps just let it run. Get comfortable ahead of time with a stool, knee pads, etc. 1/2 gal to 1 gallon wouldnít be too much. Insecticides work better when put into the nest or as close as possible.

Donít do both at the same time. If you spray while baiting you are working against yourself. If youíre not in a hurry, try the gel baits first to see if they accept it readily. Iím curious. Donít bait so close to the nest that you could spark a defensive reaction. With gels and stations you can bait within a foot or so safely. When we use granular baits weíve been taught to bait 5-10 feet away as a perimeter around the nest. The act of granules raining down on active ants will provoke a defensive reaction where they carry the bait away which made us think that this stuff is great! Look how quickly they are accepting it! When in reality they were carrying it away right in front of us...

Keep us posted.

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