The most venerable sycamores encountered by the early settlers were 500 to 600 years old, with decayed, hollow interiors. Pioneers could stable a horse, cow, or pig in one, or shelter a whole family until the log cabin could be raised. Canoeists should know that a dugout canoe fashioned from sycamore by the early French in Illinois measured 65 feet long and, depending on which version of the story you believe, weighed or could carry 9,000 pounds.
|The useful Sycamore. |
Pioneers used hollow sycamore trees for shelter.
This small example grows a short walk above
the Island, near Lock 7, by the riverside.
|Barred Owl sunbathes in Sycamore|
crotch next to the canal (arrow).
Sycamore foliage, like the trunk, is generously proportioned. The tree's genus name, Platanus, may come from the Greek platys, meaning broad, for the wide leaves. The species name, occidentalis, meaning western, is a designation that the famous eighteenth-century taxonomist Carolus Linnaeus, who named the tree, used more than once to distinguish North American plants from their European cousins -- in this
|Eagle's nest above Great Falls.|
As good a host as sycamore is, its generosity does not extend to its flower or fruit structure. Its tiny blossoms are clustered in balls, both sexes on the same tree, male clusters separate from female. The meager blooms, which are dull in color and scentless, make no attempt to lure pollinators with nectar or flashy colors. Sycamore casts its pollen to the wind, and must produce plenty of it to ensure that some reaches female flowers on neighboring trees.
Many other eastern trees, including oaks, beech, walnut, birches, and elms, are also wind pollinated. Along with sycamore, they belong to an evolutionary line that arose from primitive, insect-pollinated flowering plants more than 100 million years ago, in areas that had alternating wet and dry seasons. In adapting to that climate, the trees became deciduous, shedding their leaves each dry season. During the leafless periods, the flowers were exposed to wind, and these species adopted wind pollination. These characteristics permitted the trees to venture out of the tropics, where flowering plants had originated, to drier, colder, temperate regions. There they were leafless during the cold season. Plants were sparse in these cool regions, and wind-pollinated ones quickly expanded their range and diversified, eventually dominating. But by about 80 million years ago, insect-pollinated plants also began to adapt to temperate climates. Their efficient exploitation of insect pollinators drove wind-pollinated plants into a decline in numbers and diversity. As insects and flowering plants continue to co-evolve, wind-pollinated trees may become even more restricted, yielding to plants with scented and showier blossoms, pollinated by insects. Thus, sycamore flowers may not be dressed for success over the long haul.
|"Our" swing tree, a short walk, paddle,|
or swim upstream from the Island.
The Potomac valley in winter reveals one of sycamore's more distinctive features: The bark on the upper trunks and branches is smooth and mottled, pale greenish-gray to yellowish or chalky white (some call it "camouflage" bark), in contrast to the drab grays of the other trees. Older bark of sycamore is dark, thick, and fissured. Stream valleys can be traced in winter by the zones of white-crowned sycamores lining them.
Sycamore fruits, clustered in balls that dangle from long stalks into the winter, are also distinctive, and, like the flowers, spare and dull colored. The tiny nutlets (technically, achenes), so tightly packed in the balls, cast their lot with the wind, like the pollen. They are not fleshy, like pawpaw or persimmon, which reward a hungry animal who takes the trouble to carry off a fruit and its contained seeds to new sites. Each sycamore nutlet has a fringe of brown, silky hairs at its base to help send the nutlet sailing on the breeze when the ball begins to break apart in late winter or spring.
|White trunks stand out in winter, showing|
the profusion of Sycamores in the bottom-land.
Palisade above Little Falls, looking from Virginia.
Appropriately enough, Sycamore Island's eponymous tree still grows abundantly there. Since the canoe club's founding in 1885, many of the island's trees have been allowed to grow, so some are even becoming venerable and hollowed out. Rocky, the island's resident raccoon, knew all about it.
Jane Hill, on the waiting list, especially enjoys swimming from the Island. She is a botanist and an accomplished birder, and for the last few years has been known as "The Voice of the Naturalist" for the Audubon Naturalist Society.