Saturday, July 5, 2014

A Living Treasure

Behold the Humble Milkweed. A keystone species if there ever was one. 

Asclepias syraca is native to Canada, the great plains of the United States, and much of the eastern US. The common name, milkweed derives from the thick white sap that oozes from every part of the plant when it is broken. It's sticky and a little difficult to remove. But this plant was used extensively by indigenous peoples as a medicinal and nutritious although laborious and boring source of food. WARNING: milkweed requires intensive preparation before it can be ingested. It contains multiple substances that are toxic to humans and livestock. But this plant has found its place in the natural world.

Its waxy flowers provide sweet nectar for several species of insect. Above we see a pair of daddy-long-legs and smattering of ants. Did you miss the second daddy-long-leg? Look closer. One is on each flower ball in the second photo.

Back to those toxins. Monarch Butterflies owe their entire life cycle to this once common plant. In fact, the milkweed is the only plant on which they lay their eggs. The larvae emerge and feed exclusively on the plant, absorbing the toxins that accumulate and protect the next form of the monarch. Those iconic orange and black wings warn insect eating predators of the distasteful meal fluttering past. The strategy works so well that other butterflies mimic the color pattern to garner the same protection without having to anchor their existence to the milkweed. 

But there's a weakness in this plan. Milkweed is considered a weed by many. It's a hardy plant that can grow in almost any soil as long as it has plenty of sun, but humans still push it to the edge. Yes, it can become invasive, but as a plant that plays a pivotal role in a beautiful and fascinating Monarch's life, it is worth protecting. 

Behold the humble milkweed. Without it, our lives would be diminished. 

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