Common Names: Formica genus, wood ants, mound ants, thatching ants, field ants
This is a catch-all for ants in the Formica genus, which can be hard to separate by photograph alone. Ants of this genus tend to be between 4 and 8 mm long. As the name wood ant implies, many Formica species live in wooded areas where no shortage of material exists with which they can thatch their mounds. Wood ants typically secrete formic acid.