Showy milkweed (Asceplias speciosa)

Showy milkweed is a herbaceous, flowering perennial from Apocynaceae (dogbane) family, sub-family Asclepiadoidaea. Asclepias speciosa is just one a few species we have in Oregon: Asclepias fascicularis, Asclepias cryptoceras ssp. davisii, Asclepias cordifolia. They are found throughout most of western North America and grow in grasslands, dry prairies, road sides, along water ways, and in meadows. I was so happy to catch this milkweed visited by a swallow tail butterfly in Tanner Springs Park! One of the coolest parts of milkweeds is their flower anatomy and pollination mechanism. There are two important features to look for on milkweed flowers, the corona and corolla. The corona is a five hooded-horn structure that encloses the anther and its pollonia. Pollonia are small packages of pollen that pollinators attach to and transport between flowers. Typically, flowers produce singular grains of pollen, but milkweeds and orchids, use this mechanism to increase pollination success. Under each hood is a stigmatic slit that pollinators pry open using their legs or mouthparts to reach the nectar and pollen. If the insects aren’t large/strong enough, they get snagged and die on the flower. Showy milkweed corona have five elongated pinkish-white hoods that point outwards, kind of like a star. The corolla are made up of five fused petals that flare backwards on the backside of the milkweed flower. In the willamette valley, they bloom in umbellate clusters between May and September. The flowers mature into hairy fruit pods that break open and release its seeds called coma. The coma are wind dispersed, white, silky, and have small hairs that aid in dispersal. The leaves are elongated, simple, pointed, hairy, softly matted, pale blue-green and opposite. Ecologically, they are an important source of nectar for bees, wasps, ants, flies, and butterflies. Showy milkweed is one of a just a few species that host monarch butterfly, dogbane tiger moth and queen butterfly larvae. Monarch butterfly populations have been in decline due to decreasing milkweed habitat, so collect some seeds and plant some 🐛