Ephemeral Wildflowers of Appalachia: Living the Rock N’ Roll lifestyle
The Spring Wildflowers in the Appalachian Mountains are rebels and gamblers who are constantly playing the odds in order to gain a competitive advantage. In a region with so much diversity this is what has to be done in order to reach that ultimate goal: reproductive success. If they gamble and win these flowers get to feast and reproduce to their hearts delight. If they gamble and lose they may have to wait an entire year to get another chance but, thanks to millennia of evolution some of these plants have adapted few tricks up their sleeve to give them that slight edge that could make the difference.
As the sun first warms the forest floor, one of the most remarkable wildflowers is the first to emerge, Symplocarpus foetidus or the Skunk Cabbage. One can take a guess from its common name that, yes, this is one stinky plant. This is to attract the insects that do its reproductive bidding while basking the flesh and feces smelling nectar. Yum. However, this is actually not the coolest thing this plant does. Skunk Cabbage is actually an evolutionary anomaly in that it can regulate its own body temperature by increasing its metabolic rates (Knutson, 1979). Yes, you heard correctly. It’s practically a warm blooded plant (although not technically). The temperature of the spike of flowers, which are insulated in a “Styrofoam like” hood for better heat retention, has been recorded to be 31 degrees Fahrenheit ABOVE the outside temperature, which is enough to even help it melt through snow that may still be on the ground (George Constanz, 1995).
Skunk Cabbage isn’t the only ephemeral that takes advantage of the abundant radiation warming the floor. Many of the early wildflowers are white, disc-shaped, flowers that move as the sun does to their shape to reflect the Sun’s rays back onto the reproductive parts of the flower in order to lure more insect pollinators (Constanz, 1995). Examples of these are the Spring Beautys (Claytonia sp.), Bloodroot (Sanguinaria Canadensis), Hepatica (Hepatica sp.), Rue Anenome or (Thalictrum thalictroides), Oconee Bells (Shortia glacifolia) Cutleaf Toothwort (Dentaria laciniata), and Star Chickweed (Stellaria pubera). These little solar ovens create a perfect microclimate for a cold insect to get a bite to eat.
True ephemerals have long life spans, returning year-after-year, but they only grow for a short amount of time each year (Constanz, 1995). This is due to the cost-benefit analysis of their gambling lifestyle. If they can bust through the ground, find plenty of sun to eat before other plants grow and shade them out, attract plenty of insects to pollinate them, and avoid freezing, then they gambled and won. The trade-off is that once the tree leaves have come out to shade them, they decide that, since they can’t hog all of the sunlight unto itself then it’s going to just die back to the ground and return the next year. Bloodroot (Sanguinaria canadensis) is particularly vulnerable to the timing of their bloom and the risks and benefits that come with this method of survival. They’d rather live the short rock-and-roll lifestyle than to squabble in the shade and be outcompeted. I call it the 8-year-old “If I can’t win all the time then I don’t want to play anymore….cause ya’ll are cheaters” method of survival. Why work so hard maintaining your leaves if you’re only going to break even in the energy game. They’re just going to wait until the next spring when they can come out, outcompete all of the other plants who haven’t even emerged yet, pray it doesn’t snow (unless you’re the Skunk Cabbage), and then retreat to the ground until they can come back and dominate again. What a lifestyle.
Constanz, G. Hollows, Peepers, and Highlanders: An Appalachian Mountain Ecology. 2nd Ed. Morgantown: West Virginia University Press, 2004
Knutson RM. 1974. Heat production and temperature regulation insects that bring pollen to the flowers, and this reward in eastern skunk cabbage. Science 186, 746–747