“All animals get their energy directly from plants, or by eating something that has already eaten a plant.” www.bringingnaturehome.net
Plants photosynthesize – they use energy from sunlight and carbon dioxide from the air, along with nutrients and minerals absorbed from the soil, to grow. Other than photosynthetic bacteria and cyanobacteria, plants are the only organisms on Earth able to do this. The rest of living creatures depend on the sun’s energy too, but first it’s captured and stored in the leaves, stems and roots of every plant. This is as true for aquatic creatures as it is for those living on dry land. In lakes, ponds, streams and rivers, algae and submerged plants are the grass and shrubs of the aquatic world.
It’s not pleasant to be eaten and so plants have evolved many different ways to avoid becoming someone else’s meal. That can include physical features such as thorns and hairs or defensive chemicals that make them taste badly. Over time, though, there are always a few critters that figure out how to get around those defenses and eat the plant. In some cases, these grazing species develop a taste for one, and only one, species of plant – think monarchs and milkweeds. If that plant disappears or goes extinct, so do all those creatures who have come to depend on it.
And that’s where native plants become important – local insects have evolved to eat local native plants. When native plants are replaced by non-natives, often from different continents, the local grazers don’t recognize the new plant as food or may not be able to get around its defenses. The local grazers eventually starve or leave. Anything that eats the locals also has to find out a new food source or die. Doug Tallamy, author of Bringing Nature Home notes that native oak trees in the mid-Atlantic states where he conducts his research, support more than 500 species of insects. Gingko trees, originally from China and a popular suburban tree, only support 1. The decision to plant gingko and not oak flows right up the food chain – local bird species can’t feed their babies because the caterpillars and insects they usually catch disappeared once there were no oaks to eat. With no food for their young, the birds will leave too.
Here in Vermont, we’ve recognized that healthy lakes need shoreland plants, shrubs and trees. They filter out pollutants, prevent erosion and feed other creatures living in and around our lakes. But not just any plant will do – our native insects, birds and mammals need our native plants to survive and thrive. So, as you bring more vegetation to your lakeshore, consider your native winged, feathered and furred neighbors and plant the species they depend on.
For more information on native plants for Vermont’s lakeshores, visit the Lakewise Resource page.
To learn more about Dr. Tallamy’s research and why native plants are vital to our ecosystem, watch Doug Tallamy on YouTube or visit www.bringingnaturehome.net