Early fall ant swarms

Editor’s note: This article is from the archives of the MSU Crop Advisory Team Alerts. Check the label of any pesticide referenced to ensure your use is included.

Several people have sent in specimens of winged yard ants during the past week. Swarmers (often called allates) of several species of yard ants take flight during this time of year, often in mind-numbing numbers. Yard ants are related to carpenter ants but rather than living in rotted wood, they nest in the ground. Their colonies can be very large. The swarmers that I am seeing are reddish brown and anywhere from 1/4 to 3/8 of an inch long. Yard ants are ‘one humped’ ants, that is, they have a single hump on the skinny part between the abdomen and thorax. Like other formini ants, they also have a small circle of hairs around the tip of their abdomens. These swarms tend to be short lived, so we shouldn’t be seeing them much longer.

yard ant
This is one kind of yard ant
swarmer that someone sent in
this past week.

one hump
This photo shows the 'one humped'
nature of yard ants. it's that thing
between the abdomen and thorax
just below the wings.

hairs
This is a close up of the circle of
hairs around the very tip of the
abdomen.

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