A bright streak of yellow shines from the end of Lake Cheston. These are the morning flowers of Nymphoides peltata, the “yellow floating heart.”

These beauties are considered dangerous. They are banned in Massachusetts and Connecticut. Oregon regards them as a class A weed. Their crime is to be immigrants who tend to thrive in American waters, growing in large mats that potentially compete with other plants. I find it hard to get too worked up about this “invasion” here: all lakes in Tennessee are unnatural, made by damming streams and rivers, so the floatinghearts are just one more layer of biological novelty. Wired Mag has a nice overview of a recent provocative article in the leading scientific journal Nature that questions the scientific and ethical merits of the current anti-exotic species bandwagon.