Weeds. Just the mention of the word conjures up visions of hours of backbreaking labor. But not all weeds require our direct intervention. Our ponds, lakes, rivers, streams and oceans are virtual wildflower gardens, filled with beneficial examples of aquatic vegetation.
Peat Moss, which grows in dense greenish-brown floating carpets, is found in bogs throughout the
state. While Maine has begun to examine peat as an energy source, its largest use is as an agricultural
product. Pondweeds, which have alternate leaves and pale, spikelet-type flowers at the top, grow
densely in the deeper parts of cold-water ponds. Waterweed
Anacharis canadensis has thin green-brown leaves in whorls of three on thin stalks up to six feet tall. Its relative,
Elodea spp., is often used in aquariums. Pickerel weed is another typical pond plant. It has a showy spike of purple
flowers, leaves that look like narrow inverted hearts on upright stalks, and averages two feet in
height. In freshwater, plant life is used in part to determine whether a body of water is a pond or a
lake. A pond is defined as a shallow, calm, muddy-bottomed body of water with rooted plants that
grow even in the deepest portions. A lake, by comparison is too deep for plants to grow except at the
shoreline.
While most water lilies are found in ponds, the Little Water Lily Nuphar micropyllum grows in the deeper water of lakes. It has yellow flowers about an inch across and leaves averaging four inches in length. The petals of the flower extend an inch or two over the water's surface. If your lake has these lilies, you may want to sit quietly in a canoe and watch for turtles. Painted turtles Chrysemys picta "hang" among the lily pads with their heads out of the water. Their green and yellow striped heads look remarkably like the seed pods that are left when the flower petals have fallen off.
In the ocean, seaweeds provide food and shelter for many marine organisms. Irish Moss Chondrus crispus is used as an emulsifier in a variety of products, ranging from lipstick to toothpaste and ice cream.
Seaweeds, or algae, are different from land plants. Instead of roots, stems and leaves, seaweeds have holdfasts which serve to hold the plant in one place; stipes, which keep the plants upright; and blades, like leaves, that provide a greater surface area for photosynthesis to take place. Algae are non-vascular plants, in that they do not have an internal transport system for food and water. Since seawater contains the trace minerals and other nutrients necessary for growth, the vascular and root systems common to land plants are not required.
Macroscopic plants found in the intertidal zone are divided into four groups: blue green, green, red and brown. Blue-greens are common as gelatinous masses which cover rocks, pilings and other intertidal surfaces. Hard to identify without magnifying them, they are denoted by a blue-black color and generally slimy texture.
Sea Lettuce Ulva lactuca, a green algae, has a single blade very much like a leaf of lettuce. Enteromorpha spp., also a green, is comprised of gas-filled, ribbon-like strands that keep it upright underwater.
Coraline algae Corallina officinalis is a common red algae which grows in branched, pinkish tufts composed of calcified segments. Dulse Rhodymenia palmata is another common red. It has a disk-like holdfast and a purple to red hand-shaped blade. Dulse is often dried and served in soups or as a chip.
Winged kelp Alaria esculenta is a common brown which has a branched holdfast, a tubular stipe, a blade with a distinct mid-rib and winglets growing at the base of the blade along the stipe. Sweet tangle kelp Laminaria saccharina is another common brown, with a branched holdfast, a tubular stipe and a single, large solid blade.
The next time you're on or near the water, take a closer look at the aquatic vegetation around you.
You'll be surprised at the color, diversity and volume of plant life which surrounds you.
Cheryl A. Page
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