Photo of a giant ragweed plant.

    Giant Ragweed

    Ambrosia trifida
    Photo of several big bluestem seed heads against a blue sky.

    Grasses

    All true grasses (species in the grass family).
    Photo of whorled milkweed flowers.

    Milkweeds

    Subfamily Asclepiadoideae
    Photo of purple milkweed flower cluster

    Purple Milkweed

    Asclepias purpurascens
    Photo of white snakeroot leaves and flowers

    White Snakeroot

    Ageratina altissima (formerly Eupatorium rugosum)
    Poisonous Icon

    Poisonous