This species is native to cold regions of Asia and Europe and was discovered in the Upper Northeast of the U.S. as early as 1908 in Massachusetts and in Maine in the 1950’s. Its range has expanded and it now is present in much of the northeast U.S. and southeastern Canada.
While it is not as aggressive as the Red Imported Fire Ant this species still aggressively defends its nests, attacking intruders in large numbers and inflicting painful stings. They are evolved from cold climates and prefer to be near wet habitats. Colonies are located under logs, in the soil, within thick grassy areas, and under other debris on the soil. A colony has multiple queens and may grow to as many as 10,000 workers. They rarely enter structures and do not tend to make noticeable soil mounds. Initiation of new colonies is primarily by “budding”, with mating / swarming flights uncommon. There is concern that these ants are displacing native ants, they interfere with the normal lives of ground nesting birds and mammals, and they cause serious interference with recreational activities by people who are stung by them.
Worker ants are fairly small and reddish brown in color overall. They are a 2-node ant with a well developed stinger. The head and most of the thorax are dull and covered with grooves, but the abdomen is shiny and smooth. The antennae are 12-segmented with the last few segments enlarged to form a “club” at the end. A pair of long, backward-pointing spines are at the back of the thorax.
Characteristicts Important to Control:
Elimination of nesting habitat for the ants will help prevent their presence, such as removal of unnecessary materials on the soil, removal of old logs and brush, mowing grasses to keep them short, and preventing unnecessary moisture that attracts the ants. Baits with a sugar attractant seem to be acceptable to the workers. Contact insecticides, particularly non-repellents that may offer a transfer effect in the colony can be successful.