Photo of whorled milkweed flowers.

    Milkweeds

    Subfamily Asclepiadoideae
    Closeup of single flowerhead of a New World aster with yellow disk florets and lavender ray florets

    New World Asters (American Asters)

    Symphyotrichum spp. (formerly Aster spp.)
    No photo available

    Philadelphia Fleabane

    Erigeron philadelphicus
    Photo of water milfoil plants along the shore of a pond

    Water Milfoils

    Myriophyllum spp.