Water Hyacinth
Aiton's Encyclopedia (1910)
wa'ter hi'a-sinth, a pond weed allied to the pickerel weed, and not very far distant from true hyacinths. There are several species. The common water hyacinth is a native of Brazil. It was introduced into the St. John's River of Florida and other Southern waters on account of its beauty. It really is a handsome plant. The leaf-stalks are inflated like bladders and are filled with air. The roots are of two sorts. Those of one kind grow along the surface of the water like runners and produce new plants; the others are thickly clothed with long root-hairs and droop downward in the water like plumes. The leaves and flower stems of each plant constitute a little group that sits daintily on the water or rides before the wind like a duck. Tourists entering New Orleans by rail are charmed with the clumps of violet blue flowers and green leaves that dance on Lake Pontchartrain. The method of multiplying by runners, however, has made trouble. A central plant is soon surrounded by others, and these by others and others again, until a large floating island is formed. These masses accumulate in the rivers and bayous of the South until navigation is seriously obstructed. So much public money has been expended in clearing the channels that the water hyacinth is derided as the million-dollar weed, and is pointed at like the English sparrow as an example of what theorists, without practical knowledge, will do by way of introducing they know not what.
What Has Changed in the Last Century
Aiton's in 1910 already called it the "million-dollar weed" for choking Southern bayous, but the scale of the problem since then has dwarfed anything Florida or Lake Pontchartrain saw. Eichhornia crassipes is now ranked among the world's worst aquatic weeds, spread across Africa and Asia; a bloom that reached Lake Victoria in the late 1980s covered thousands of hectares of shoreline and crippled fishing and ferry traffic at Kisumu before weevils of the genus Neochetina were released against it in the 1990s. It is a federal noxious weed in the United States, and mechanical clearing has largely given way to herbicides and these imported beetles. Botanists have also moved the plant, long known as Eichhornia crassipes, into the genus Pontederia — formally joining it to the pickerel weed the 1910 account said it was "allied to."
Written for this edition, 2026.