Leucanthemum vulgare

Native from Europe to Siberia and Iran, this perennial herb spreads through seeds and creeping underground stems. Each daisy head combines white outer ray flowers with many tiny yellow flowers in the central disk. A single plant can produce thousands of seeds that remain viable in soil for years. Widely introduced, it is cultivated and naturalized in Colombia. It is invasive in Washington State, where dense colonies crowd out pasture plants and reduce crop yields. The flower heads attract bees, butterflies, flies and beetles. Photographed in Bogotá, Colombia.