Attracted to Milkweed

or reflexed petals, and a five-lobed crown between the petals and five stamens. It was this familiar shape that lured me to the butterfly-infested Poke Milkweed.

The structure of the flower and its slippery surface regulate pollination. When an insect lands on a flower its feet slide around, often down between the nectar-filled points of the crown. Legs get caught in a slit where sacs of pollen, called pollinia snag the insect’s leg, and are pulled from the stamen. The pollinia must then be precisely inserted in slits behind the crown for pollination to take place. If inserted backwards, the pollen grains will germinate in the wrong direction, and are wasted.

Those who might not recognize milkweed by the structure of the flowers would probably still know Common Milkweed, either because of the large seed pods full of white silk and seeds, or the white juice that oozes from the stems and leaves when they are broken. This juice, which contains sugar, gum, fat and other compounds, is acidic and somewhat poisonous to animals - some milkweeds are more poisonous than others. Because of this, it is considered a noxious weed in some places, particularly in areas with livestock. Conversely, these poisons - cardiac glycosides - are necessary for the survival of Monarch butterflies.

Monarch larvae eat nothing but the foliage of milkweed. While I have seen them on Butterfly Weed and Swamp Milkweed, they seem to prefer Common Milkweed. Females lay their eggs on the leaves, which soon hatch. The tiny caterpillars that emerge will munch on milkweed, ingesting the cardiac glycosides that makes them, both as larvae and adults, unpalatable to predators. Birds that do eat a Monarch almost immediately become sick, and will vomit for as long as a half-hour. Some birds in the Monarch’s winter habitat have learned which part of the butterfly to eat.

It was as a food source for Monarch larvae that I first made room for Common Milkweed in the garden. Soon fritillaries, skippers, hairstreaks and even Hummingbird moths were nectaring in its flowers. As the plants spread the butterflies not only multiplied, but my yard filled with a heavenly lilac-like aroma. I had no idea this nectar-rich plant was so sweetly scented.

The joy Common Milkweed gave me eventually led me to fields and marshes where Butterfly Weed and Swamp Milkweed flourished. Soon my curiosity lured me further afield in search of other milkweed species, and each new

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