The Lasius Ants of the Pacific Northwest
Also known as meadow ants, the species spends most of its life underground in meadows and your lawns. The nests are often completely overgrown by grass, sometimes the nest sites locations can be found by looking for small mounds of loose soil material between the grass stalks.
Lasius Ants will also build nests under large rocks or concrete slabs. They will tend aphid colonies within their nests so as to feed on the honey dew that they produce, the nest site will eventually become obvious as the aphids clear sections of grass or portions of gardens.
The queen is up to 9 mm long and the males are about 5 mm and workers are up to 4 mm long. Their color varies from yellow to light brown, with the queen and males being a bit darker in color.
The yellow meadow ant feeds on the honeydew from root aphids, which they breed in their nests. During winter, the aphids themselves are eaten. As a consequence of their feeding habits, the species is seldom seen, but sometimes you can spot them when they forage outside the nest.
Winged ants can be seen on warm days and evenings of July and August. This is one of the rare times that they are seen, as workers push the young winged ants out of the nest to create new colonies, these new colonies are formed by multiple queens but later on the queens will battle until only one queen remains.