The water lily, whose scientific name is Nymphaeaceae, is one of the world’s most beautiful and recognizable plants. The water lily is the glorious floral topping to the usually frog-laden lily pad. There are two main categories of water lilies: hardy and tropical. The hardy water lily will flower and bloom only in the daylight. The tropical variety will bloom during any time of the day or night.
Though water lilies look as if they are sprouting from the water, they are actually floating on top of the water with their roots tethered deep into the water-logged soil at the bottom of the lake or pond.
Water Lily flowers are wonderfully showy and fragrant, lasting only a few days. Some open during the day and close at night, others the opposite. Most are pollinated by beetles.
The white water lily is a perennial plant that often form dense colonies. The leaves arise on flexible stalks from large thick rhizomes. The leaves are more round than heart-shaped, bright green, 6 to 12 inches in diameter with the slit about 1/3 the length of the leaf. Leaves usually float on the water’s surface. Flowers arise on separate stalks, have brilliant white petals (25 or more per flower) with yellow centers. The flowers may float or stick above the water and each opens in the morning and closes in the afternoon. The flowers are very fragrant. White water lily can spread from seeds or the rhizomes.
Submerged portions of all aquatic plants provide habitats for many micro and macro invertebrates. These invertebrates in turn are used as food by fish and other wildlife species (e.g. amphibians, reptiles, ducks, etc). After aquatic plants die, their decompostion by bacteria and fungi provides food (called “detritus”) for many aquatic invertebrates. Deer, beaver, muskrat, nutria and other rodents will consume the leaves and rhizomes of white water lily, while the seeds are eaten by ducks.
The Fragrant Water Lily (Nymphae odorata) has a unique pollination strategy. On the first day that the flower blooms, its pollen is not yet released, and instead, a fluid fills the centre of the flower, covering the female parts.
Should an insect visit the flower, the design of the petals causes it to fall into the fluid. If the insect is covered in pollen, the pollen dissolves in the fluid and fertilises the flower. The next day, no fluid is produced, and pollen is released instead. The insect that falls into the fluid usually emerges unharmed, although a few unlucky ones may be trapped and drown.
A few days after the Water Lily flower is pollinated, the flower stem tightens in a spiralling spring to bring the flower head underwater. The fruit develops underwater into a spongy berry with many seeds that are enclosed in arils. When ripe, up to 2,000 seeds are released from each fruit. Young seeds float as they contain air pockets. They are then dispersed by water currents or by water birds that eat them. As they become waterlogged, they sink into the mud to germinate. The plant also spreads by sprouting from the creeping rhizomes.
The flat round leaves have a waxy water-repellent upper side. The underside, however, seems to cling to the water by surface tension. Some Water Lilies leaves are purple underneath, the pigments helping to concentrate the sunlight to maximise photosynthesis. The leaf stem is hollow and transports air from the surface to the underwater rhizomes which can grow to a massive size. Water Lilies grow best in calm freshwater.
Uses: The American Indians made flour out of dried roots by pounding them. The flour was then baked into pancakes. The young leaves and flower buds were eaten as vegetables, seeds eaten fried.
Traditional medicinal uses: American Indians used the plant to treat many ailments. Mashed green roots were used as poultice for swollen limbs; the roots for problems of the womb, digestive problems, a rinse for mouth sores; leaves and flowers as cooling compresses.
Role in the habitat: The Water Lily’s leaves shade the water keeping it cool and thus allowing for more dissolved oxygen. The plant also provides hiding places for small aquatic creatures, which in turn attract predators such as Bitterns (see right). But in places where it has been introduced, the Water Lily can become a weed and blocking out sunlight and oxygen from the water and displacing local aquatic plants.