Green ants in Ohio? Ohio USA, not ... Thailand or Australia?
Green ants are remarkably rare, globally. The most commonly seen green ant is Oecophylla smaragdina, the weaver ant which has many green morphs.
But these would never be found under a rock or in the USA.
Lasius flavus is common under rocks in the US, and light yellow, if they ate something green such as aphids or green candy they might have looked green, or due to lighting?
futurebird