Question
QUESTION: I have 2 large cottonwood trees in my back yard, a good 50-60+ feet tall. For the past two years I have had a very annoying problem; clumps of winged, red ants falling from high up in the trees.

This seems to happen at the same time each year. I have tried using multiple types of ant bait granules, sprays, Toro traps, and some of the homemade solutions, but nothing I do seems to be killing the source. What I have been doing seems to rid me of what has falling down to the ground that day, but the next day, more ants fall from the sky.

I finally went out on my roof to see if I could see where the ants where coming from on the tree, and noticed a lot of activity happening at the very tip top of one of the trees.

Is there anything else I can do short of calling the professional, or getting the trees chopped down(an option I am looking into)? I have a very small backyard, and having it littered with these pests is getting really annoying, now into my 2nd or 3rd week of dealing with it. Makes it even worse with 2 hyper dogs that have to be leashed and let outside in the front yard.

Thanks.

Cory



ANSWER: Cory,

Sounds like you have a large carpenter ant nest in the tree. Unlike most ants, carpenter ants nest above ground in cavities. This is why they can become structural pests and damage houses. These ants are releasing so called winged reproductives, all ant colonies do this at certain times of the year. Here's a link to a page about carpenter ants http://www.livingwithbugs.com/carpenter_ants.html that may be useful. There are many species of carpenter ants so the coloration of your's may not be exactly what's pictured on that page.

Removing the tree may be the best option. I doubt that a pest control company can do much for you given that the nest is so high. I don't think there are any pesticide treatments that would be effective.

Post a follow up if you have questions.

Jack DeAngelis, PhD
Extension Entomologist (ret.)
My website about home and garden pests: http://www.livingwithbugs.com



---------- FOLLOW-UP ----------

QUESTION: Thanks Jack,

That's what I was afraid of. Luckily, they don't seem to be anywhere inside any structural part of my house, but the fear I guess is that even if the trees come down, would they still be attracted to my yard and try to nest in the walls?

Last year, the problem occured for about a month, the falling ants, and then they seemed to have went away. Is that normal for that to only occur for a short period of time, and then not see any trace of them for a whole year?

Does color make a difference in the world of Ants?

I am in Eastern Washington State, so the summer times when these ants start falling is when it is close to the 100 degree mark.  

Thanks again for all your help.

Cory

ANSWER: Taking the tree down should have no effect on whether or not a nest occurs in the house. Take a look at the carpenter ant page cited above and the page linked from that page for ways to inspect for carpenter ants in a structure.

It is normal for the reproductive (winged) stage to be found at only one time of the year. The ants are still active but the winged stage is not.

I'm not sure what you are asking in the "color" question.

Jack DeAngelis



---------- FOLLOW-UP ----------

QUESTION: The ants I have are red. Is there a difference between the severity or treatment of red ants compared to black ants?

Thanks for all the help.

Cory

Answer
There are many species of carpenter ants. The color combinations run from all red to all black with mixtures in between. You would have to submit samples to a lab (for example at WSU) to get a species determination. There's no difference in how you treat the different species in terms of control.

Jack DeAngelis