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Invasive Species |
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Eurasian Water-milfoil |
 Scientific Name: Myriophyllum spicatum L.
Myriophyllum spicatum is a submerged, aquatic perennial that can have green, reddish-brown or whitish pink stems 6-20 ft. long. The leaves are olive green in color, and less than 2 in. long. They are soft and feather-like in texture, and each mature submerged leaf has a central midrib with 12-20 filiform segments on each side. There are both male and female flowers on the same inflorescence. The female flowers are basal while the male flowers are located distally. The female flowers have a 4-lobed pistil and lack sepals and petals. The male flowers have 4 pink petals and 8 stamens. The globular fruit are indehiscent, 0.08-0.11 in. long and contain 4 seeds.
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Variable Water-milfoil |
 Scientific Name: Myriophyllum heterophyllum
Myriophyllum heterophyllum is an herbaceous aquatic plant that has stout stems up to 0.1 in. in diameter. The leaves are green and in whorls of 4-6. There are two types of leaves. The highly variable emergent leaves are bracts and can reach 4-6 in. above the water. These leaves are stiff and can be serrated to lobed along the margins, lanceolate or lance-spatulate to elliptic. These emergent leaves are 0.2-1.2 in. long and 0.06-0.2 in. wide. The submerged leaves are feather-like, pinnate, 0.8-2 in. long and 0.75-1.5 in. wide. They have 4-10 paired pinnae. Mudflat forms have 4-5 paired pinnae. The flowers are small, and the reddish, oval shaped petals are 0.0625-0.125 in. long. The fruit are subglobose in shape, have a scabrous texture and are 0.04-0.05 in. long and wide. Each of the mericarps is 2-ridged on the back but rounded on the sides, and is prominently beaked. The fruits and flowers appear from June-September.
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Carolina Fanwort |
 Scientific Name: Cabomba caroliniana
Cabomba caroliniana is a submersed, rhizomatous, aquatic perennial that can have stems up to 6.5 ft. long. It has two types of leaves. The petioled, submersed leaves are opposite, and sometimes whorled, peltate in form, and are 0.75-2 in. in width. These leaves are repeatedly divided into filiform segments. The small floating leaves are few and linear-elliptic in shape, have entire margins and often have a basal notch. These leaves are 0.25-0.75 in. long. The long-peduncled (1.2-4 in.) flowers are most often white with yellow at the center, but are rarely pink or purplish. The sepals and petals are about 0.5 in. across. The petals are auriculate at the their bases, and obovate in shape. The 3 ripened carpels are flask shaped.
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Non-Invasive Species |
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Chara |
 Scientific Name: Chara spp.
Although these common lake inhabitants look similar to many underwater plants, they are actually algae. Muskgrasses are green or gray-green colored algae that grow completely submersed in shallow (4 cm) to deep (20 m) water. Individuals can vary greatly in size, ranging from 5 cm to 1 m in length. The main "stem" of muskgrasses bear whorls of branchlets, clustered at regularly spaced joints. When growing in hard water, muskgrasses sometimes become coated with lime, giving them a rough gritty feel. These algae are identifiable by their strong skunk-like or garlic odor, especially evident when crushed. Six to 16 leaf-like branchlets of equal length grow in whorls around the stem, and are never divided. These branchlets often bear tiny thorn-like projections, which give the plant a rough or prickly appearance when magnified. The round, stem-like structure varies from 5 cm to over 1 m in length. Since Algae does not produce flowers, instead microscopic one-celled sex organs called oogonia are formed. These tiny organs and patterns in the cases that surround them are used to distinguish between species. Muskgrasses may be attached to the bottom by root-like structures called holdfasts.
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Nitella |
 Scientific Name: Nitella sp.
Nitellas are bright green algae that often are mistaken for higher plants because they appear to have leaves and stems. These long, slender, delicate, smooth-textured algae lie on the bottom of a lake or pond and are seldom found in the water column. Whorls of forked branches are attached at regularly spaced intervals along the "stems". Nitellas sometime grow together with muskgrasses (Chara spp.), another plant-like algae, to form underwater meadows. Six-eight evenly forked branchlets grow in whorls at regularly spaced intervals along the "stem". Unlike the rough branchlets of most muskgrasses (Chara spp.), nitella branchlets have a smooth texture. Hollow, stem-like structures have whorls of forked branches along their entire length. The largest nitella species have "stems" up to 2 m long. Since Algae does not bear flowers, instead nitellas have microscopic spore-producing organs. Male organs grow at the base of the branchlets. Female organs are located in a cluster on the sides of the branchlets below the male organs. Roots may be attached to the bottom by root-like structures called holdfasts or floating free.
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Bladderwort |
 Scientific Name: Utricularia spp.
Bladderwort is the common name given to the plants of the genus Utricularia. The largest genus of carnivorous plants, it consists of some 215 species which occur in fresh water and wet soil across every continent except Antarctica. Bladderworts are cultivated for their flowers which are often compared with those of snapdragons and orchids. All bladderworts are carnivorous, and capture small organisms by means of bladder-like traps. Terrestrial species tend to have tiny traps, and feed on minute prey such as protozoa and rotifers swimming in water-saturated soil. However, in aquatic species such as the Common Bladderwort U. vulgaris, the bladders are large (sometimes exceeding 5 mm in diameter) and can feed on more substantial prey such as water fleas (Daphnia), nematodes and even fish fry, mosquito larvae and young tadpoles. Despite their small size, the traps are extremely sophisticated. When prey animals brush against trigger hairs connected to the trapdoor, it is released and the bladder sucks in the door and the prey, along with the water surrounding it. Once the bladder is full of water, the door closes again, the whole process taking only ten to fifteen thousandths of a second. Bladderworts are unusual and highly specialized plants, and the vegetative organs are not clearly separated into roots, leaves and stems as in most other angiosperms. The bladder traps, conversely, are recognized as one of the most sophisticated structures in the plant kingdom.
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Waterweed |
 Scientific Name: Elodea canadensis
Young plants initially start with a seedling stem with roots growing in mud at the bottom of the water; further adventitious roots are produced at intervals along the stem, which may hang free in the water or anchor into the bottom. It grows indefinitely at the stem tips, and single specimens may reach lengths of 3 m or more. The leaves are bright green, 6-17 mm long and 1-4 mm broad, borne in whorls of three (rarely two or four) round the stem. It lives entirely underwater, the only exception being the small white or pale purple flowers which float at the surface and are attached to the plant by delicate stalks. It is dioecious, with male and female flowers on different plants. The flowers have three small white petals; male flowers have 4.5-5 mm petals and nine stamens, female flowers have 2-3 mm petals and three fused carpels. The fruit is an ovoid capsule, about 6 mm long containing several seeds that ripen underwater. The seeds are 4-5 mm long, fusiform, glabrous (round), and narrowly cylindrical. It grows rapidly in favorable conditions and can choke shallow ponds, canals, and the margins of some slow-flowing rivers. It requires summer water temperatures of 10-25 °C and moderate to bright lighting. It is closely related to Elodea nuttallii, which generally has narrower leaves under 2 mm broad. It is usually fairly easy to distinguish from its relatives, like the Brazilian Egeria densa and Hydrilla verticillata. These all have leaves in whorls around the stem; however, Elodea usually has three leaves per whorl, whereas Egeria and Hydrilla usually have four or more leaves per whorl. Egeria densa is also a larger, bushier plant with longer leaves.
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Pondweed |
 Scientific Name: Potamogeton spp.
Potamogeton, commonly called pondweed (note that not all pondweeds are Potamongetons), is a genus of aquatic, mostly freshwater, plants of the family Potamogetonaceae. Plants are mostly perennial and typically produce rhizomes which are the common over-wintering form. Many species also produced specialised overwintering buds called turions which may be borne on the rhizome, on the stem or on stolons from the rhizome. The leaves are alternate, which contrasts with the closely related genus Groenlandia where the leaves are opposite or whorled. In many species, all the leaves are submerged and in these cases the leaves are typically thin and translucent. Some species, especially in ponds and very slow moving waters, have floating leaves which tend to be more leathery. Diagnostic of most species of Potamogeton is the presence of a delicate membranous sheathing scale at the leaf axil. This may be wholly attached, partly attached or free of the leaf and it may have inrolled margins or appear as a tube. The flowers, which are often overlooked are composed of 4 rounded segments borne in a spike. Potamogeton species are found throughout the world where there is standing or running water. There are estimated to be around 90 species but hybridisation provides an added complexity to the taxonomy. Not all plants called pondweed are in the genus Potamogeton. "Canadian pondweed", Elodea canadensis, which shares some characteristics, is , for example not a Potamogeton.
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White Waterlily |
 Scientific Name: Nymphaea odorata
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.
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Watershield |
 Scientific Name: Brasenia schreberi
Watershield is a floating-leaved plant, but the long leaf stalks reach all the way to the bottom where they attach to a long creeping root that is anchored in the mud. Watershield is occasionally found in lakes, ponds and slow streams from the northern counties of Florida, south to the central peninsula. It prefers water up to six feet deep. Watershield leaves are oval and shield-shaped. Its leaf stalks are attached at the centers of the leaf blades. Its submersed parts and undersides of leaves are covered with a viscous jelly-like substance. Its flowers are small, dull purple, and emerge from the water on a stalk.
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Cat-Tails |
 Scientific Name: Typha latifolia
Typha latifolia (Bulrush, Common Bulrush, Broadleaf Cattail, Common Cattail, or Cat-o'-nine-tails) is a perennial herbaceous plant in the genus Typha, which grows in temperate, subtropical and tropical areas throughout the Northern Hemisphere. It grows in marshy areas and flowers in mid to late summer. The common cattail shares its range with other related species, and hybridizes with Typha angustifolia, narrow leaf cattail, to form Typha x glauca (Typha angustifolia x T. latifolia), white cattail. Common cattail is usually found in shallower water than narrow leaf cattail. The plant is 1.5 to 3 meters high and it has two to four centimeters broad leaves. The rhizomes of Typha latifolia were eaten by many first peoples of North America, as well as the leaf bases and young flower spikes. The rhizomes can be consumed after cooking and removing the skin, while the peeled stems and leaf bases can be eaten raw or cooked. While Typha latifolia grows all over, including in rural areas, it is not advisable to eat specimens deriving from polluted water as it is used as a bioremediator, it absorbs pollutants. Do not eat them if they taste very bitter or spicy.
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Tape Grass |
 Scientific Name: Vallisneria americana
Wild celery (Vallisneria americana) is a plant in the family Hydrocharitaceae (the "tape-grasses"). Contrary to the implications of its name, wild celery bears little to no resemblance to the Celery one may buy at the market. Wild celery grows under water and is consumed by various animals, including the Canvasback. The plants themselves are long, limp, flat, and have a green mid-ridge. Animals may eat the entire plant (both the leaves and the underground tubers).
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