Saturday, April 4, 2009

Skunk-cabbage

First Wildflower
© Dave Spier

At least one wildflower doesn't care what the weather is doing. It can produce its own heat from chemical reactions inside the plant, a process called thermogenesis. This ability may have evolved in early plants during the age of dinosaurs (the Mesozoic) as a way to entice insects to pollinate the primitive flowers. The heat helps the flowers to mature so they can launch odors attractive to insects and provide warmth if the insect spends the night. Later, it can keep the embryonic seeds from freezing during cold snaps.


If you know where to look, this wildflower has been visible since last fall when its pointed greenish-gray tips poked through the mud and leaf litter. It grows in wetlands mostly around the edge of swamps and along stream banks. In late winter the stalkless flower hood, called a spathe, swells and turns maroon or sometimes it's mottled with light green. It resembles cupped hands with an opening on one side and the pointed top may curl over. Inside is a light-yellow ball, called a spadix (or club) that looks like a small golf ball, but instead of dimples, the surface sprouts bumps that are the actual flowers. I'd recommend not looking too closely because the odor has been likened to carrion or dead meat. Then again, it's not for our benefit. It attracts carrion flies as well as bees and gnats which overwinter as adults. Instead of getting nectar, which more highly evolved flowers produce, the insects receive warmth at a time when it's in short supply.


The flowers appear before the leaves because the long root stored enough food the previous summer. The tightly coiled leaves, bright spring-green in color, rise next to the flower hoods and open into a rosette of broad, egg-shaped paddles. Their job is to nourish the seeds and produce an excess of food that can be stored underground for the following spring. Again, I'd recommend not getting too close because the crushed leaves smell like skunk. By now you've guessed that we're discussing Skunk Cabbage, a widespread plant of the bottomlands. It's also been called Polecat-weed, Bear's-foot, Fetid Hellebore, and Midas-ears. Native Americans called it Skunkroot, but were able to eat it by boiling in three changes of water. Early Swedes called it "bjornblad," Anglicized to Byron-Blad, meaning "bear's leaf," a reference to bears eating it in the spring. Makes you wonder about the bear's sense of smell...

Skunk Cabbage is a member of the Arum family, so it's a relative of Jack-in-the-pulpit and Calla Lily. By the time these latter species appear, the spring migration will be well underway and we'll be enjoying warm weather. Or will we? Stay tuned and have faith; spring will arrive. It's inevitable, like the amount of daylight increasing. If you ignore twilight, the length of day and night are both 12 hours around March 20, the date marked on the calendar as the beginning of astronomical spring. It's enough to trigger the return of blackbirds and other hardy migrants that spent the winter a few states to the south, even if they do run into an occasional late snowfall in Upstate New York.

Part of the spathe removed to show the actual flower inside...
 
There is a range map for this northeastern species at:
http://plants.usda.gov/java/profile?symbol=SYFO
...and a related west-coast species called American Skunkcabbage:

Send your comments, questions, or suggestions to Dave Spier, northeastnaturalist@yahoo.com or request hyperlinks to my photo websites. There's a link to my Facebook page at the bottom of the right sidebar.

(This copyrighted blog is based on an article that first appeared in the Times of Wayne County, March 24, 2008. All photos © Dave Spier. All rights reserved. A similar version appeared in a
Montezuma Audubon Center newsletter.)