Skunk Cabbage - The Nature Institute

Skunk cabbage has now receded into the earth. A fully-grown skunk cabbage has a massive root system (Figure 5). It’s virtually impossible to dig a plant out of the ground. (I’ve tried.) A few inches into the ground the leaves grow out of the top of a thick roundish stem, called a rootstock or rhizome. Out of the rest of the rootstock the roots grow. Many roots, up to the thickness of a pencil, grow out of the rootstock in all directions. There is no taproot. The roots have virtually no branches until near their tips, where they ramify into many small, fibrous rootlets.

The roots are wrinkled in a regular, ring-like pattern. This shows that they are so-called contractile roots. The roots grow and then contract, actually pulling the plant deeper into the mucky, dense soil. Skunk cabbage is a perennial. The seeds germinate on the surface, so that at the outset the rootstock, which gives rise to the roots, is also above ground. As the roots grow and contract, they pull the plant downward. Year by year skunk cabbage becomes more deeply anchored in the ground. Large, older plants lie correspondingly deeper than younger ones. No one knows how old an individual plant may become. In any one population you will find small plants with only one or two leaves — perhaps a few years old — next to plants four feet high with numerous leaves and perhaps decades old.

In the same wetland where I observe skunk cabbage, its close botanical relative, the wild calla (Calla palustris), grows. It always grows where water stands most of the year, while skunk cabbages grow where it’s a bit drier, often emerging from small hillocks created by tree roots, old stumps or trunks of fallen-over trees. Before the wild calla plant flowers from mid-May on, its leaves resemble somewhat in size and shape those of a young skunk cabbage. But in contrast to skunk cabbage, you can easily pull a wild calla out of the soil. Its horizontally growing stem puts forth small roots that barely penetrate the surface of the mucky soil. The plants are essentially suspended in water, hardly rooted in the soil.

This contrast highlights skunk cabbage’s pronounced feature of being so deeply and firmly rooted in the soil. The vibrant and lush growth of the leaves has its complement in the strong subterranean anchoring. The roots and rootstock store large amounts of nutrients that make rapid and exuberant growth of the leaves in spring possible, while the photosynthetic activity of the large leaves allows the storage of nutrients for the coming years. Bound to a very moist environment, skunk cabbage is deeply and intensely rooted in the soil, making the lush growth of this largest woodland wildflower possible. In contrast, the semi-aquatic wild calla barely reaches into the soil and remains a much smaller plant.

Rounding the Circle

When skunk cabbage’s flowers have been pollinated, the fruits begin to grow. The flower head swells and develops into a fruit head (Figure 6). The spathe withers and dies, and the stalk that carries the fruit head elongates, growing along the surface of the ground. By mid-June the fruit heads are roundish balls, about two inches (5 cm) in diameter. They usually have the deep, wine-red color of the spathe. The fruit heads house numerous round, berry-like fruits, each containing one seed. In August the fruit head falls apart. The fruits lie on the ground — to be eaten, to decompose, or to germinate (either in the fall or next spring).