Thursday, March 27, 2014

The Risks of Spring

Sunny wildflowers one day, cold and snowy the next. There's an old word for the kind of weather we've been having: Spring. It was only 18º on the back porch yesterday morning, but the wildflowers seemed happy enough when Beth and I went for a saunter once the sun got up.

The earliest-blooming wildflowers seem to be adapted to withstand cold-snaps. They are usually low to the ground, have simple flowers, and little or no leaf surface exposed. Most of them can also shut their blooms closed against the cold night air. I'm not sure why, but they (almost) all have white flowers.

As they say, "timing is everything," and this couldn't be more true than it is for the spring ephemerals. This group of wildflowers squeeze their entire blooming cycle into the narrow window between persistent cold and perpetual twilight.

As the forest thaws and soil temperatures rise, the waiting underground parts of these plants spring into action and send shoots, leaves, and flowers upward out of the soil and into the sunlight. Here the brave plant urgently grows and blooms in a race against the green darkness coming when the forest canopy is unrolled and the forest floor is plunged into perpetual twilight.

Early in the season, this balancing act between cold and sun is complicated more by the scarcity of available insect pollinators. It will do the plants no good to open their flowers before pollinators are available. Many spring ephemerals can open and close their flowers, exposing pistil and stamens when the sun is shining and insects are active and closing shut again when it's cold and pollination is unlikely.

With the weather being variable as it is, life is always a gamble and there are always individuals willing to test their luck and courage. There are always outliers. Within a species and within a population, you can always find one or two individuals willing to risk it all by being a little early or a little late. Sometimes it works; sometimes it doesn't. Freezing temperatures or debilitating darkness can quickly put these rouge individuals back in their place.

Of course, the spring ephemerals always have one more tactic at their disposal: Patience. Even if the winds of fortunate ruin all hope of sexual reproduction, the perennial root-stock will just wait and try again next year. Despite the brevity of their above-ground existence, most spring wildflowers are several years old, blooming from the same root system year after year after year. In fact, some wildflowers (e.g., Pink Lady Slipper) are known centenarians, having a fresh beauty that belies their true age. As long as they're left alone, they can always live to bloom another year.

A friend once pointed out that "you only get so many springs," and I am trying to heed her encouragement and see all that I can each year. I think we take spring wildflowers too much for granted. They live richly varied and complex lives, and most of us know little about them. Indeed, even though I can name many of them on sight, I have more questions than answers. Why do some grow here and not there? Why are all the early flowers white? How old do they live to be? Why are some ubiquitous and others rare? Why are some extravagantly beautiful and others obscurely dull?

Each spring the wildflowers call me into the forest to behold their wonders and ponder their mysteries. Wildflowers challenge me to seize the day; each moment is fleeting, and I never know how many I'll get.

Cutleaf Toothwort (Dentaria laciniata)
Cutleaf Toothwort (Dentaria laciniata) soaking
in the sunshine after an overnight low of 18ºF

No comments:

Post a Comment