Origin:
Native to the western United States, where it is found commonly along the western Sierra Nevada mountain range at low elevations.
Biology:
This is a close cousin to the Velvety Tree Ant, but often behaves much like carpenter ants, by excavating cavities within structural wood members. Large accumulations of fine sawdust-like frass are pushed from these nests onto surfaces below. Foraging workers are most often found on trunks of trees, particular pine trees, feeding on other insects and on honeydew from plant feeding pests. Exterior nests will almost always be in wood, such as rotting root systems of trees, hollow trees, old stumps, etc.
Identification:
These are single node ants with workers all the same size, about 4 mm long. They are shiny black and easily confused with Odorous House ants. However, on the Pine Tree Ant the node is visible from the side. It has an evenly rounded thorax, no circle of hairs around the anal opening, and when crushed the workers give off a distinct odor.
Characteristicts Important to Control:
Control of most ants includes correction of the attractions that drew them to a property, including harborage sites, food sources, and moisture conditions. Elimination of insects that provide protein or honeydew sources reduces ant foraging in an area, very important for this species. Ant bait products in granular, liquid, or gel formulations can be effective, and protein baits may be preferred. When the ants are nesting within a structure the nest needs to be located and treated directly, with residual dust insecticides very effective.
