Back in the day, that is about 130 million years ago, during the Cretaceous Period, there was a spectacular co-evolution of flowering plants and pollinators, mostly insects. Flowering plants, the angiosperms, make up about 80% of all plants on earth. They include all plants with conspicuous flowers, such as daffodils, violets and lilacs but they also include plants with less obvious flowers such as crab grass, birch trees and cattails. 10-20% of flowering plants are wind pollinated, relying on the vagaries of wind to carry pollen to a nearby female flower. But most flowering plants rely on animals, especially bees, butterflies and other insects, to pick up male pollen and deposit it on the stigma, the female part of the flower, for successful pollination. Most flowers attract these pollinators with fragrant scents, and energy-rich nectar and pollen as rewards for visiting flowers. But this is life, and some flowers don’t play by the rules. Here are three examples: one stinks, one cheats and one is downright treacherous.
Skunk cabbage, Symplocarpus foetidus is found in wet woods and along streams throughout northeastern North America although I have only seen it once. It flowers very early in spring, and it has two tricks. First, as its name suggests, it stinks. When bruised or broken, all parts of the plant give off a skunky smell. Second, the plant generates its own heat, with temperatures 30 to 60F higher than the surrounding air temperatures. It will melt the surrounding snow as its flower emerges from the ground. The heat not only helps melt the snow to allow the flower to emerge but also probably helps waft the skunky smell through the air, attracting pollinating flies and bees. To go along with its fetid smell, it has a mottled purple and brown hood-like flower, maybe looking and smelling somewhat like a dead carcass to attract the sorts of insects entranced by that kind of thing.
If skunk cabbage reneges on the promise of pleasant-smelling flowers, Calapogon tuberosus, or grass pink lures pollinators but offers no reward for their efforts. Grass pinks are strikingly beautiful magenta-colored orchids common in sphagnum bogs and other wet places in early spring. Typical of orchids, the flowers are elaborate with extravagantly complicated wing-like and lip-like petals, but they produce no nectar. The top lip of the grass pink is vertical; with a fringe of bristly knobs that attract the bees. Bees alight on this bristly lip which is hinged at the base and the weight of the bee causes the lip to fold down until it is touching the lower lip. This somersaults the bee onto the female part of the flower, the stigma, where the bee is stripped of any pollen it might have been carrying. It then slides onto the male part of the flower, the anther where it may pick up a package of pollen. The bee flies off, possibly having pollinated the flower, but it has gotten nothing but a bit of a tumble for its trouble. The grass pink upper lip pops back into its vertical position to wait for the next victim, I mean bee. Researchers believe it is only young, naïve bees who fall for this deception, but I have no idea how they know this.
Although bees that pollinate the grass pink might not get a reward, at least they are not harmed. Insects that pollinate white pond lilies, Nymphaea odorata, often do not survive the pollination experience. These white-petaled pond lilies are common in our lakes, floating and flowering through most of the summer. Each pond lily flower opens for three days but for insects visiting the flower on day one, it may be their last. On the first day, the petals are mostly tilted toward the center, creating a kind of tunnel of petals. The flower produces a little puddle of viscous liquid at its base, though it isn’t sweet enough to be considered nectar. The stigma, the female part of the flower, is located under this puddle and is receptive to pollen only on day one. Not realizing it is a trap, insects enter the tunnel of petals and head for the liquid at the bottom anyway. Any pollen the insect may be carrying is washed off in the liquid and the pollen fertilizes the receptive stigma. While some insects escape, many drown and never make it out of this puddle of death. Happily, on days two and three, the flower is completely open, and insects visit the flower unmolested and carry away pollen.
Enjoy the coming spring and summer and remember that each flower and each animal play a part in the gob smacking diversity of life on this planet. As Darwin said, “There is grandeur in this view of life.”
