Virginia Meadow Beauty (Rhexia virginica) is growing in thick mats over the Lake Cheston spillway. The flowers have exaggerated, twisted stamens whose bright yellow contrasts with the purple petals. The stamens hold pollen which is gathered by bumblebees using “buzz pollination”. The bees grab the stamens, then vibrate the muscles in their thorax to make a buzz that causes the stamens to release pollen. In this way, the plants keep pollen thieves away, allowing only reliable bumblebees to carry away the cargo. Tomatoes are pollinated in the same way — stand next to a tomato plant and listen to the short zaps as bumblebees work the plants.

Virginia Meadow Beauty

Welcome bumblebees

These delicate mushrooms were growing in the decomposing litter at the side of the trail. Their caps are pleated and paper thin, held up with impossibly thin stalks.

Parasola plicatilis (formerly Coprinus plicatilis) seen from below. They stand about four inches high.

Top view of the parasols.

This species has all the classic “bean family” characteristics:

Flowers with a big upper banner and two lower lips

Leaves in clusters of three

and fruits in a pod. This particular species has pods that stick like velcro to passing animals.

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.