Vol. 18 Issue 1, Spring 2013
by John DeMary
When European settlers sailed into the Chesapeake Bay they found a landscape dominated by dense forest and inhabited by a variety of native people. The interior forest seemed dark, dangerous and forbidding to the new arrivals, when actually it was a treasure chest of plants that provided food, medicine and other resources for the native people. These plants had evolved strategies to survive in an environment dominated by numerous species of gigantic deciduous trees.
Before Europeans began clearing the ancient forest, there were few breaks in the endless canopy, requiring plants of the forest to complete for light intensity, pollinators, moisture and limited resources.
Completing the floral cycle early enough to avoid the mature canopy exposed plants to a variety of weather extremes, but growing close to the ground, the ability to protect floral parts, and fast development were successful strategies. If conditions are not favorable for pollinators, plants like spring beauty and bloodroot remain tightly closed. When sunlight is available, floral parts can be warmed by the reflection from white petals. The flower of skunk cabbage actually generates an internal temperature much warmer than the surrounding air temperature, providing a winter haven for potential pollinators.
Numerous consecutive days when early spring temperatures are over 50° ensure a wide variety of pollinators will be attracted to the only floral show available. The bumblebee’s ability to fly at lower temperatures than most other insects (41°) makes it the most useful pollinator for early spring wildflowers.
The lack of a rain-blocking tree canopy provides plants on the forest floor with an abundance of moisture to be absorbed by roots or captured on pubescent stems and leaves. The difference in moisture availability with a lacking canopy may be more important than light intensity to early spring wildflowers.
The scat of various mammals and birds carries seeds of many plants, but ants are the preferred distributors of fertile seeds for 30 percent of forest wildflowers. In a process called myrmecochory, the insects are recruited into service with a tasty morsel called an elaiosome, which is attached to the seed. Ants may carry seeds quite a distance before devouring the fat-filled elaiosomes and discarding the seeds, often safely underground.
Once flowers are pollinated and seeds are produced and distributed, it is time to become dormant for another season. Much of the photosynthetic energy produced during abundant sunlight has been stored underground in bulbs, rhizomes or corms, ensuring a new generation. These structures also serve as nutrient sinks, allowing plants to store high concentrations of nitrogen, phosphorus and potassium needed for rapid development the following spring. As the mature canopy filters 90 percent of the available solar energy, mosses, ferns and tall broadleaf plants dominate the forest floor, while native wildflowers sleep and await another brief but spectacular display.
Why the excitement over spring wildflowers? I think Senegalese poet and conservationist Dioum Baba said it best:
“In the end,
We will conserve only what we love,
We will love only what we understand,
and we will understand only what we are taught.”
Excitement for spring wildflowers is fostered by an understanding of the delicate balance maintained between the life of the flower and the life of its forest habitat. To know the flower you must know the forest, and to know the forest you must know the flower. This understanding might create a love that could help conserve a precious habitat in the end.
Abundant wildflowers can be found throughout the summer and fall, but these plants are hardier and can grow in acres of abundance, or cracks in pavement. Many thrive because of disturbance, and their blooming life is long and obvious. While the summer and fall plants flaunt their beauty in the long days of sunshine, a small corm, bulb or rhizome lies hidden beneath the forest floor, storing enough energy and nutrients for a brief but spectacular flash to reproduce another generation—therein lies the excitement of spring wildflowers.
References:
Marion Lobstein, “Spring Wildflower Ecological and Life Cycle Information,” Northern Virginia Community College, Manassas, VA.