keep the wildness on your desktop

If a science fiction writer were to imagine what the “perfect plant” would look like and how it would grow, protect itself and reproduce, whatever she came up with probably wouldn’t be as good as the real life common milkweed (Asclepias syriaca).

While we often use the term “weed” to designate a plant that is bold enough to grow where humans don’t want it to grow, that term often names plants that are so good at growing that they avoid human control and survive our mowings, sprayings, pulling and other assaults.

Common milkweed is a native prairie and meadow plant, but unlike many other natives that dwindle and die out when humans change the landscape, milkweed continues to thrive in the disturbed places in forests and fields. That is because milkweed has an amazing set of adaptations that allow it to thrive in unlikely locations.

Once milkweed gets established, it is almost impossible to dislodge. This plant has a deep taproot system that digs down more than a foot into the soil. If you try to pull the plant out, the root breaks and sends up a new stem a week later. On roadsides, where milkweed are common, mowers cut down adult plants, only to see them growing again a few weeks later. What’s more, milkweed roots can spread laterally and send up new sprouts.

Milkweed flowers perfume the air during July and August. This smell attracts insects who feed on flower nectar from the plant’s pink flowers. When insects leave the flowers, they are often carrying pollen on their legs. They carry the pollen and pollinate other milkweed plants as they feed.

Once insects pollinate the flowers, a milkweed grows crescent-shaped green seedpods. When the pods split open in August, the seeds blow on the wind on silken “parachutes” and blow far and wide. Some of these hundreds of seeds land on dry soil and sprout into new plants. This wind distribution technique allows one milkweed plant to spread its seeds far and wide in a field or roadside.

But growing and spreading seeds aren’t the only things that a plant must do. It also has to survive grazers like deer, moose and snowshoe hares. Milkweed protects itself from grazing by producing a bitter latex in its stems and leaves. This “milk” tastes bad to herbivores, so they leave the plant alone. Incidentally, monarch caterpillars feed on milkweed plants and store the chemicals from the bitter “milk” in their bodies. Those chemicals give the caterpillars and adult monarch butterflies a bitter taste and in turn protects them from predators. Once again, truth is stranger than science fiction.

Source: Timberjay - www.timberjay.com