Among members of the Aster family, the fern-like foliage of Yarrow is rather unusual and it has a distinctive odor. Other members of the Aster family with this kind of foliage include Anthemis spp. (Mayweed), Matricaria spp. (Chamomile), and Tanacetum vulgare (Tansy). Unlike Yarrow, species of Mayweed and Chamomile produce daisy-like flowerheads with long petaloid rays. Tansy is a larger plant with medium to dark green foliage. While its flowerheads have a similar size and structure as compared to those of Yarrow, they are bright yellow and their petaloid rays are even smaller in size or absent.