'Milkweed in Winter.' Drawing by Carolyn Newberger

Illuminating the Hidden Forest, Chapter 28: The miracle of milkweed

A veritable banquet for ants, flies, bees, wasps, beetles and butterflies, milkweed’s best-known customer is the monarch butterfly.

To read the previous chapters of ‘Illuminating the Hidden Forest,’ click here.

Jan. 8, 2020

On the edge of our small lake, each spring, a milkweed plant, or two or three, emerges from the soil. Quickly, they shoot up stalky stems with elongated rubbery leaves and milky sap, and then explode with clusters of pink flowers. Later, their pear-shaped prickly pods burst at the seam, sending cottony seeds flying and floating into the wind.

Though milkweeds are a widespread species with many variants in other climates, several are native to New England. Indeed, with its abundant seeds and tenacious rhizomes, common milkweed (Asclepias syriaca L.) is an enthusiastic spreader and often treated as a weed to be eliminated. As a consequence, milkweed is much less abundant than in the past. This is a pity.

The “weed” in its name notwithstanding, milkweed is a miracle plant to be treasured and even cultivated. Milkweed connects us both historically with an ancient past and geographically across a continent. Its Latin name, Asclepias, is for the Greek god of medicine. Milkweed’s medicinal purposes have included using its milky sap to treat such human problems as warts and lung disease.

Tipping its clustered cap to the pathophysiology of the insect world, milkweed’s poisons, when imbibed by certain insects, render them poisonous to birds, which, consequently, don’t eat them.

A veritable banquet for ants, flies, bees, wasps, beetles and butterflies, milkweed’s best-known customer is the monarch butterfly. Monarch butterflies need milkweed to lay their eggs, and their caterpillars eat only milkweed foliage. If we lose our milkweed, we lose our monarch butterflies. Milkweed also aids monarchs indirectly. Even though monarchs don’t absorb enough of the milkweed’s poisons to be poisonous to birds, the birds don’t know that, and so don’t eat our monarchs.

Monarchs are something of a miracle themselves, flying each year up to 3,000 miles to winter in Mexico and California. They are the only butterfly species with seasonal migrations like birds.

Common milkweed habit, from ‘Weeds of the Northeast by Uva, Neal and DiTomaso, Cornell University, 1997.

But the monarchs are endangered, both by the effects of climate change and by losses of their milkweed habitats. Nonetheless, we can help. Let’s cherish our milkweed and grow more. Although common milkweed needs to be grown in places where spreading is not a problem, seeds of noninvasive native milkweeds are widely available for purchase and are not hard to grow.

So at this moment, in the heart of a blustery Berkshire winter, I am thinking about spring, and growing more milkweed. I am also looking forward to placing my palm beneath a strappy leaf, and feeling, through this plant, our enduring connections across time, space and species.

For more information about milkweeds and monarch butterflies, here are two good places to start: the National Wildlife Federation (https://www.nwf.org/Garden-for-Wildlife/About/Native-Plants/Milkweed, https://www.nwf.org/Educational-Resources/Wildlife-Guide/Invertebrates/Monarch-Butterfly; and UMass Amherst (https://extension.umass.edu/landscape/weeds/asclepias-syriaca).