Rockcliffe Park. These barberry flowers appear in late spring, stay for a brief time and are replaced by the more noticeable red fruit. Barberry is a non-native species, imported for use in gardens. In some areas it can be a very serious invasive species and its sale, forbidden. So far, around Ottawa, it doesn't appear to be a big issue, but that could change. I'm certainly finding it more and more in natural areas.