Spring brings skunk cabbage

#MIDDLEBURY

Skunk cabbage flowers resemble Jack-in-the-Pulpit when they first emerge. The flowers appear before the large green leaves. (Curtiss Clark photo)

By JANINE SULLIVAN-WILEY

When you think about the glories of early spring, many blossoms come quickly to mind. This plant is probably not one of them. But this amazing and utterly unexpected plant – skunk cabbage – is one of the most important of the spring plants.

As Curtiss Clark, who photographed today’s featured plant, has noted, “Symplocarpus foetidus is indeed fetid.” How can something so stinky, and not terribly attractive, be so interesting and truly valuable?

First, this native plant blooms in very early spring, although you might not realize that those emerging shapes contain flowers. A member of the Arum family, which includes calla lilies and elephant ears, its flowers appear before the leaves. They erupt from muddy ground that is often still icy or snow-covered, with a maroon or purple shape called a spathe that forms a hood around the actual flowers – the spadix. There is slight resemblance to its relative, the Jack-in-the-Pulpit.

Their most unique characteristic is now visible; ice and snow melt around the emerging flowers. While at this flowering stage, skunk cabbage can maintain a core temperature in those hoods of 70 degrees, much higher than the surrounding soil and air. They can maintain that warmth even as the temperatures plummet over night. They are able to do this through an oxidative process in which they metabolize oxygen at a high rate much like some tiny mammals do.

The skunky odor is most noticeable if you step on the plant, but that odor has its own important function: it attracts insects. Gnats pollinate skunk cabbage, as do – no surprise given their smell – carrion beetles and flesh flies (yes, flesh flies are real insects). These insects in turn form an important food source for birds that rely on very early spring insects for food.

The plants’ leaves contain an especially large percentage of water and are eaten by several species of moths. They are not suitable for consumption by humans or many other animals for that matter, but they are eaten by bears. (One has to consider how hungry bears are, though, after a long winter of food-less hibernation.)
Happily, this is not a plant one would want to remove as it has a deep and tenacious root system. The main rhizome can be a foot long and 3 to 6 inches wide, surrounded by fibrous roots. Each year the roots contract and pull the plant deeper into the ground.

When the leaves emerge, they do so in a lovely spiral pattern, growing wide and green and often covering the wet areas in which they grow. You can see them now, the leaves unfurling in wetlands along the Greenway and in Middlebury Land Trust properties. By late June, the leaves begin to die but not like autumn leaves that fall to the ground and dry up. They first develop holes, and then get slimy and dissolve away, rather like something left too long in the back of the refrigerator. By August, they are gone, only to have their warm magic bring them back in the very early spring the following year.