It’s very common to have a plant or animal seem obviously harmful to one group of people and obviously benign to another. Take cats. “Cats are introduced all over the world. They have massive impacts on native songbird populations. But nobody in their right mind would classify them as invasive and try to control them,” Cadotte said. “I mean, except Australia.”
There are plenty of other examples. Take those salmon introduced to Lake Superior and prized by many sport fishermen. The state of Minnesota regulates the size and quantity of salmon you can catch, which helps keep their numbers stable. The Grand Portage Band of Lake Superior Chippewa, on the other hand, treats salmon as an invasive species that it wants gone. There’s no limit on how many of the fish tribal members can catch. In the past, the tribe has actually killed non-native sport fish in its streams in order to more effectively stock those streams with native trout, said Seth Moore, director of biology and environment for the Grand Portage band.
Another example: The earthworms that live in the soil along the shores of Lake Superior are invaders from Europe, and while they’re great for gardens, they alter soil quality in forests and make those ecosystems less hospitable to native plants, said Stuart Reitz, professor of entomology at Oregon State University. In other parts of the country, beekeepers and ranchers have fought bitterly over whether an invasive flower, called yellow starthistle, should be considered generally beneficial (because it is to bees) or generally harmful (because it is to livestock), said Mark Hoddle, director of the Center for Invasive Species Research at the University of California, Riverside.
This isn’t just trivia. Invasive species control is always expensive, and you only get the resources to launch a full-court press against a plant or animal — like the hundreds of millions of dollars spent in the last six decades to get sea lamprey populations under control — on the rare and shining occasion when everyone in power agrees on what “harm” is.
James Landreth wrote:Sudden oak death syndrome is ravaging native plants here (including rhododendron, evergreen huckleberry, etc). Yet people continue planting oaks. It makes me sad that they're wasting time, money, labor, and water on it. Sudden oak death syndrome is spreading in Europe too.
There are seventy kids in my school district who go hungry every weekend. I sure wish people were planting walnuts and chestnuts instead of oaks that will fail. If it's not in your area in the Pacific Northwest it soon will be.