Ants do not have noses. Rather, they detect scent through very sensitive chemoreceptors on their antennae. This is how ants can zero in on the food crumbs that you forgot to sweep up. But you can also use ants’ olfactory sensitivity to your advantage. There are certain scents that ants find off-putting or that signal danger to them. (vinegar, thyme, citrus peel, lavender, chrysanthemums, coffee grounds, cinnamon,)
