Question
Its been a year and I am losing the battle against ants in my oak trees. I live in Fresno foothills. The ants are black with some red on them and they bite bad. I've tried: Sevin, grant's, terro, and garden sprays. I can't get up into the trees. I can only treat where Ican reach andthey are happy being up in the trees, then swarming again when the poison moves, or they just change their path. There are huge trails from tree to tree. I've contact arborist at Fresno State, who referred me to CA Growing Concern, no one knows what to do.  I'm afraid over time these trees will fall down. Could you give me a treatment plan?  Thank you!

Answer
The velvety tree ant is named by its velvety abdomen and habit of nesting in trees. There are a number of different species, however, on particular species, the California velvety tree ant (Liometopum occidentale), is the principle pest to humans. They are attracted to sweet baits. A sweet bait such as Drax Liquidator may be useful. Baits are used since the workers will carry some back to the nest a feed it to the queen and this will kill the nest. Contact insecticides will work BUT all you are killing is the workers that are present. These ants are hard to control. I think I would contact a local pest control company and ask them if they can rid the tree and your property of velvety ants.