What's going on with these ants?

[ancjr]

I found a Sassafras infested with ants and dying near where this picture was taken earlier this year, I cut it and burned the infested wood.  Now, I see this nearby:

It looks like herbicide burn-down to me?  I've never seen ants do this before!

[Shotgun]

The damage is caused by aphids.  The ants are only tending the aphids.

[SwampDonkey]

x 2

[ancjr]

Thanks guys.  Spraying them with soapy water is an option?

[Shotgun]

ancjr - Soapy water is an option, however I would suggest that you contact the Indiana cooperative extention service (Purdue Univ.) for current recommendations, if you feel that it's worth the effort.  You'll get the best info there.

[ancjr]

Thanks again!   

[wmrussel]

What did you find out from the extension?  What did you end up doing?

[ancjr]

They're just on the one tree, which I believe is an ash.  Didn't call the extension or act on my own... had other pressing issues.

[ancjr]

I had a change of schedule and went ahead and called Purdue.  They advised me that the aphids/ants will tend toward trees that are already in decline.  The agent did not know off the top of her head what would be the best course of action or chemical treatment if they did spread to other trees, but promised to call me back after she had time to research it.   8)

Update:

Permethrin or Pyrethrum containing insecticide, applied via label or insecticidal soap was recommended.  Seems there is a lot of pressure from EAB here, along with other insects and disease which follow suit to quickly annihilate any and all Ash.  All the living Ash trees on the property are less than 2" DBH and 10ft tall, none but the newest seedlings look at all healthy.   :-\