Friends of Beaver Pond Park (FoBPP) is a volunteer organization whose goals are to improve the natural features of the park. We are affiliated with Urban Resources Initiative (URI), a not-for-profit university partnership whose mission is to foster community-based land stewardship, promote environmental education, and advance the practice of urban forestry.
Berries Of Winter
Remaining berries of winter are a valuable food source for a variety of birds. Mel Evans — Associated Press
By Kathleen Kudlinski
Ever wonder why so many fruit are red or purple? Or why poison ivy leaves turn scarlet so early in the fall? Or why sumac berries are still clinging to their bushes long into February while others are long gone?
None of these things are accidents. They all evolved to help the plants survive. Plants do not make fruits and berries (including pumpkins and cranberries) for us to eat. Fruits are designed as bait. The plants are fishing.
The worst place a seed can sprout is under its parent. It can’t hope to compete, since the mature plant already has control of the light and soil in that spot. And if all of a plant’s seeds fell to the ground, they could attract seed-eating mice and insects, dooming a whole generation.
So plants must scatter seeds, a tough order for an organism that can’t move. To do so, they hire the locomotion specialists, animals, to do their seed dispersing for them. They use energy as the “coin” for payment.
It takes a lot of energy to produce a fruit, but plants must ensure the survival of their species. Energy-rich fruits are the payment a plant gives an animal for carrying its seeds away.
The fruit is digested and the seed falls, intact, in a dropping far from the parent plant. The shiny red and purple of most fruits are the want ads soliciting the services of hungry birds.
During the summer, plenty of protein-rich insect food is available to birds. To compete, summer-fruiting plants pack their berries with sugar, a quick source of energy. Strawberries, blackberries, blueberries and the like are high-sugar fruits.
Many fall fruits and berries have a high fat content, instead. These are “high-quality” fruits, because there is more energy (calories) in a mouthful of fat than a mouthful of sugar. Birds, with their high metabolic rate, love high-fat berries, so there is a ready clientele to help disperse these seeds.
But high-fat berries take much more energy to produce. They also tend to rot quickly. The plants with these berries have to sell their wares rapidly. That is why most of them become ripe during fall migration. What better seed-disperser could a plant hope for than a migrating bird?
Poison ivy and Virginia creeper have high-fat berries. They advertise their wares to the earliest fall migrants with brilliant red leaves. Dogwoods, spicebushes and sassafras have high-energy fruits, too.
Other plants depend on birds that spend the winter here. These birds get really desperate for food, so their services can be bought cheaply. Look over the woodlands and roadsides now. The fruits still hanging in late November and onward are “low-energy, low-fat.”
That also means they rot more slowly. Some of them, like sumac berries, last right through to spring, and are eaten by returning migrators. You see the sumac berry bunches by roadsides and in empty lots, held aloft by the sumac’s antler-shaped branches.
Have you ever eaten a sumac berry? Don’t bother. They aren’t poisonous, but the only flavor is bitter-tart. We’re used to thinking of berries as sweet, but those are spring and summer fruits. Sumac berries have one purpose: to last out the year and be planted in the spring. To protect against insects that might go after the meager nutrients, sumacs coat their berries with stiff fuzz.
Are these fruits of any good for us? If you are desperate, you can make a sumac-aid as Native Americans did, by steeping the withered, fuzzy red berries in hot water. Their tart flavor permeates the now rosy water, but, sweetened with honey, it could be a stand-in for tea. Chilled, it makes an interesting option to lemonade — if you are really thirsty. But sumacs do not bear fruit for us.
They are out there, doing exactly what they’re supposed to do — being a berry of last resort.
Guilford naturalist Kathleen Kudlinski is the author of “Boy, Were We Wrong About Dinosaurs,” Dutton, grades 2-5, as well as 40 other children’s books. Contact her at email@example.com or c/o the Register. Drop by www.kathleenkudlinski.com right now for a quick, daily nature note at my POND SIDE PLACE blog/website, or visit my writer’s group at http://writeupouralley.com/, or watch my “Horse Indian Wolf” book video at http://www.youtube.com/watch?v=psR4UGFSVe8