Flora Fact: Floating Flesh Eater
The bladderwort gobbles down tiny animals that get too close.
By Sheryl Smith-Rodgers
Sometimes nature can be downright sneaky ... and bizarre, too. Take floating bladderwort (Utricularia radiata), for instance. This East Texas aquatic plant survives by chowing down on microscopic animals that just happen to bump into it.
Found in the shallow waters of ponds, lakes, ditches and marshes, floating bladderwort — which lack roots — resemble a small wagon wheel with a flower stem stuck in the middle. The inflated stalks, which form the wheel's spokes, support lacey masses of submerged leaves, all dotted with small round bladders called utricles.
Here's the sneaky part: Sensitive, hairlike projections surround the utricle's closed trapdoor. Water fleas, protozoa and other passing organisms that touch the hairs instantly trigger the flattened bladder to open. Like a suction bulb, the utricle inflates and inhales both water and prey. The trapdoor snaps shut, and the plant then secretes enzymes, which dissolve the organisms into nutrients.
Such bizarre behavior characterizes most carnivorous plants. Of the five major groups of flesh-eating plants found in the U.S., four are native to Texas: bladderwort, pitcher plants, butterworts and sundews. The well-known Venus flytrap grows wild in the southeastern U.S.
Despite its somewhat gruesome nature, floating bladderwort does have a pretty side. From March through July, the upright flower stems produce four to 17 bright yellow blooms.
