Ants are tiny insects and may be black, brown, red, or yellow. Adult ants range in size from as small as 1 millimetre (1/16 to 1/32 inch), like little black ants and thief ants, to as large as 13 millimetres (1/2 inch), like carpenter ants.
Most ants commonly found in Canada are not aggressive, although some can sting. Ants should be tolerated as much as possible since they cause little damage in the garden. They can even be considered beneficial because they eat other insects like young silverfish and moths.
Species known to invade homes in Canada include the carpenter ant, the little black ant, the odorous house ant, the thief ant, and the pharaoh ant. Pavement ants can become a nuisance in lawns, gardens, and pathways, as well as indoors.
Carpenter ants are larger than other species, although the sizes of the workers vary. They can cause structural damage to homes as they destroy wood to make room for their nests. Piles of sawdust may mean you have carpenter ants.
Ant colonies send out scouts to search for food. Ants are attracted to many types of food. They enjoy eating sugary and greasy foods (like peanut butter or crumbs) and are also attracted to the "honeydew" produced by aphids on infested houseplants. A successful scout leaves a scented trail for other workers to follow back to the food source.
Removing access to food and water is the easiest way to avoid pest problems:
Source: Health Canada