Ants will fall for this natural indoor insect repellent and head back outdoors pronto.
In answer to Mary Ezzell's request in TMEN NO. 4 for a natural indoor insect repellent: She might start with ground cinnamon, which repels ants in the house. I sprinkle it along the kitchen windowsill and around the mouse's cage and have actually watched ants retrace steps and leave.
Make sure you have an even layer of the cinnamon and not just clumps that the ants can walk around. I imagine other spices — such as oil of clove or red pepper — will work as well, but keep a sharp lookout for new routes that the little pests will possibly find. They are determined!
Insects are like blades of grass that manage to take root in city sidewalks — proof that man cannot escape nature nor live separately from it.
(Country Lore, September 1970)