Thatching ants are fascinating insects. As the days get shorter and the temperature starts to drop activity at the thatching ant (Formica spp.) mound begins to change. Early in the cool morning there is little happening on the surface. A few ants move slowly around the entrance holes, arranging fir needles and other bits of woody and plant debris. Later as the day heats up the mound more ants emerge and the activity becomes more frenetic.

While most people don’t like ants I find them quite fascinating. Thatching ants are entertaining to watch and are beneficial in controlling other insects. In addition, many species of birds visit the mound to use the ants for “anting” in an effort to rid themselves of skin parasites. I enjoy sitting and watching a mound at work – there’s something meditative about it!

Note the diagnostic notch in the thorax of the ants in the photographs above and below. This is one feature that differentiates the mostly benign thatching ant from the more problematic carpenter ant.

This video shows the ants in action!