Under the massive canopy of an oak tree, mounds of uprooted grass line the pavement of the parking lot waiting to be stuffed into garbage bags. A group of volunteers, blissfully unaware of a light rain shower under the protection of the natural umbrella of the tree, use their shovels and hands to yank up the deep roots of Guineagrass, an invasive plant species in Texas, originating in Africa.
The small group is helping to mechanically remove invasive plant species from an area around a cluster of ancient oak trees at Goose Island State Park in Rockport. The Guineagrass has become so overgrown that the live oak trees, native to Texas, are now competing for the same space.
Invasive plant species are those that are not native to an environment. “Native,” in this case, is defined as any organism that has occurred naturally in a particular area without having been introduced by human activity. Non-native species, plant or animal, travel from one place to another through humans and our products by car, boat and even plane.
Ecosystems are composed of different organisms interacting with each other. Humans are a part of ecosystems, not separate from them. We rely heavily on what’s provided through an ecosystem – oxygen, water, healthy soil to grow our food and pollinators – like birds and bees – that nourish fruits and vegetables. Healthy ecosystems are a result of native wildlife interacting with native plant species, a relationship formed over thousands of years, so the introduction of non-native species can disrupt that ecological harmony.
The most environmentally friendly way to remove non-native plant species is through mechanical removal, which can be done by hand, on a small scale, by machine, on a larger scale, or even controlled fires.
Once something has been changed, it’s impossible to completely undo that change and make it as if the change had never occurred. As Tom Waits famously sang, “You can’t unring a bell.” The same can be said about the environment. And though we can’t completely prevent the spread of non-native species to other parts of the world, there are small things that people can do to promote biodiversity and allow native plant species to flourish.