Spring in the Air

SkunkCabbageHorizBy Laurel Hamers ’14

The Berkshires’ earliest-blooming wildflower isn’t one you would pick for a bouquet. Instead, it’s a pungent plant that grows in wet, swampy areas—Symplocarpus foetidus, the skunk cabbage.

On a recent Tuesday, students in biology professor Joan Edwards’ Field Botany class took advantage of a warm day to see—and smell—this unusual plant in action. In a marshy field off Potter Road in south Williamstown, they clustered around the blooms poking up through melting snow.

Skunk cabbage flowers have a unique structure: They cluster on a fleshy stem called a spadix, which is enveloped by a mottled purple sheathe called a spathe. Most other plants with this structure grow only in the tropics. “We’re very lucky to have a member of this family native to our area,” said Edwards.

The skunk cabbage blooms before other flowers in the area because it acts like a furnace, produces its own heat to power through frozen ground and snow. By burning the sugars and starches stored in its large taproot, the plant can reach temperatures of up to 70 degrees Fahrenheit. The warmth melts the surrounding snow and, when coupled with the plant’s rotten meat-like odor, attracts insect pollinators.

Its smell alone might be enough to keep potential grazers away, but the skunk cabbage has another defense up its sleeve: Its large, innocent-looking leaves contain idioblasts, specialized cells packed with double-pointed glass crystals. Any animal that takes a bite will soon regret the decision as the needle-like shards tear into the lining of the animal’s throat and digestive tract.

Back in the lab, Edwards carefully sliced in half two skunk cabbage inflorescences collected from the field to demonstrate another feature of the plant. Its flowers are female in early stages of development and then become male. Students’ curiosity overpowered their aversion to the smell (more noticeable in a small classroom than outdoors), and they crowded around microscopes to see the difference between the tiny white female flowers and the yellow male ones.

“Most people have no idea plants can heat up, change sex, and defend themselves with an arsenal of weapons, but skunk cabbage does all three. It is truly a botanical wonder,” said Edwards.