music
ambience: Dawn chorus, Sierra Nevada
A weed by any other name is still a weed, but only in the eye of the beholder. I’m Jim Metzner and this is the Pulse of the Planet.
“When a plant is a weed depends upon what you’re managing for. If you’re a farmer, you might want to be growing corn, and in that case, a native plant’s a weed. If you’re a rancher, you’re going to be trying to grow a nutritious blend of grasses on your ranchland, so that you can have cattle be happy.”
Barry Meyers Rice is an invasive species expert with the Nature Conservancy. Here’s his take on what a weed is.
“We are managing for native biodiversity, and a weed is a plant that decreases biodiversity. You can have a plant being a marvelous garden plant, but then it can turn into a weed when it escapes from a garden, and starts propagating itself in a wildlands situation. So then a gardener might say that’s a wonderful plant, but for us in the biodiversity business, if it escapes in a nature preserve, and starts occupying too much territory and starts cutting down on biodiversity, that’s when a plant can change from a desirable plant into a weed.”
But an invasive weed can do more damage than just crowding out other species.
“Another kind of a plant that can really cut down on the biodiversity is a plant that might completely change the natural processes that are present. It might change the way that a natural fire moves through the system. . . or it could change the way that water moves through a system . . . or it could change the way that nutrients in the soil behave. And so these are things that can completely change the ecosystem, and not just occupy a lot of space by crowding out other weeds.”
We’ll hear more on weeds in future programs. Pulse of the Planet is presented by the National Science Foundation. I’m Jim Metzner.
music