Credits

Created by Virginia Pellington, Christina Prehn, and Robert Copus, Explore Natural Communities Interns Summer 2016, NatureServe.

Sounds: Rushing Stream 2, recorded by mike_stranks (freesound.org). Licensed under Creative Commons:  Attribution-NonCommercial 3.0. Rushing Water 2, recorded by misty_audio (freesound.org). Licensed under Creative Commons: Attribution-NonCommercial 3.0.

Music: Montauk Point by Kevin MacLeod, modified (incompetech.com). Licensed under Creative Commons: Attribution 3.0.

Photo: Herbaceous Depositional Bar, by Milo Pyne, courtesy of NatureServe. Licensed under Creative Commons: Attribution 4.0.

Reference:
Willow Bark

Transcript

Podcast time: 2:40 minutes

In our world, change is inevitable. It's happening everywhere around you. If you look hard, you can find a great example of change along the shore of Virginius Island in Harpers Ferry. Located beside the Shenandoah River, this strip of land is always changing. Floods violently churn up the shoreline, making it an unstable home for most plants! The plants that do thrive here are well-adapted to living with change. Some grow quickly and spread their seed before another flood hits. Many have excellent root systems that anchor them in the ground to stay put when forceful waters might otherwise tear them from the landscape. The shoreline looks different from place to place, with patches of different kinds of vegetation. But, these different natural communities have a lot in common, and we can refer to the shoreline communities of Virginius Island collectively as “Herbaceous Depositional Bar.”

In some places along the shoreline, the receding floodwaters dump piles of broken twigs and branches. While smaller plants struggle to grow past the heavy debris, one small water-loving tree does not have a problem getting started here—and it’s called the black willow (Salix nigra). Even though trees are not typical of the unstable Herbaceous Depositional Bar, you can sometimes find patches of young black willow taking root along the shore of this island in Harpers Ferry. They may or may not last long here.

Did you know that the bark of the willow tree has the chemical composition of aspirin? Using willow (Salix spp.) was very popular in Ancient Egypt and Greece. Patients may have chewed on the bark to relieve pain or fevers. Today, willow bark may still be used to treat these conditions. However, modern day aspirin has added different chemical compounds, which help people with a wider range of ailments.

Do you notice how the black willow trees and other vegetation tilt in the direction that the river is flowing? Previous powerful floodwaters caused them to lean downstream. The frequent flooding either uproots them entirely or forces them to grow permanently in this direction. If they’re able to hold on long enough, these young black willow saplings will eventually grow a dense mat of fibrous roots to hold soil in place, creating a more stable patch of shoreline. These shoreline natural communities are an impressive image of unrelenting change!

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