We haven't seen any ants since.
However, while researching this dilemma (we refuse to use pesticides), we found all sorts of eco-friendly suggestions.
posted originally from: AT:San Francisco
Since we can't find the nest to pour boiling water on it, we're more drawn to the tips that involve sprinkling products on the ant trails. Some of these are: aspartame, black pepper, borax, catnip, cayenne pepper, chili powder, cinnamon, crushed mint, cucumber, a mixture of baking soda and powdered sugar, or citrus peel and water, or white vinegar and water. If the ants return, we think the idea that we'll try is to spray peppermint or spearmint essential oil on the trail.