I once heard a visitor refer to coastal Texas — somewhat humorously — as “The Land of Ugly Waters.” On the upper coast, our rivers flow muddy and dark, staining our bays and giving us dull, brown beaches. Even the Gulf of Mexico is affected by the rivers’ silt. When fishermen begin reporting that clear, blue water has moved within a few miles of the shore, high excitement ensues.
Even our freshwater ponds tend toward murkiness during most of the year. But in winter, as cold temperatures and less light slow plant growth, the surface clears, and visibility increases.
Last weekend, the waters at a freshwater pond in the Brazoria Wildlife Refuge were so clear it was possible to see the bottom, where the plant commonly known as Broadleaf Arrowhead (Sagittaria latifolia) had begun its underwater growth.
Named for its arrowhead-like leaves, the plant can be found submerged in shallow water or on wet muddy banks along sloughs, swamps, marshes, and ponds throughout North America. Each plant produces leaves and flowers on separate stalks. Above the water’s surface, its leaves tend to broaden, while submerged leaves tend to be more narrow. Their three-petaled white flowers are easily distinguished; male flowers have bushy yellow centers, while the centers of female flowers are smooth and green.
The plant also is known as Duck Potato because of edible tubers that form at the ends of its rhizomes. Enjoyed by waterfowl and other animals such as muskrats, they also can be boiled or baked and eaten like potatoes by humans. An important food source for Native Americans, they sometimes were known as Wapato.
Accustomed to seeing the plants’ rich green foliage and delicate flowers, it was a delight to catch a glimpse of their secret underwater life.
In time, light and warmth will obscure the pond’s bottom as algae blooms and plants such as duckweed begin to increase on the water’s surface. But by then, both leaves and flowers will be full and tall, providing a new way to enjoy the plant.