Freshwater Plants

Marsh
green marsh

Tim Ervin

Aquatic plants are plants that have adapted to living in aquatic environments. These plants grow in or near water and is either emergent, submergent, or floating. In lakes and rivers, they provide cover for fish, produce oxygen, and act as food for some fish and wildlife. They have a significant effect on soil chemistry and light levels as they slow down the flow of water and capture pollutants and trap sediments.

 
Cattail
Cattails in the marsh

Tim Ervin

Cattails


Cattails are good for river ecosystems, as their roots keep the soil along the banks from eroding. Fish, birds, and insects all use cattail plants for shelter. Their roots can even remove certain pollutants from any nearby water! Leaves are linear, light green to brownish in color, thick, sword-shaped, and flat with a sheath near the base. About 12 to 16 leaves can arise from one individual shoot and the flower head is spikelike and dense. The top cluster of each flower is packed with small male flowers, and the bottom of the flower was clustered with small female flowers. Cattails are usually found in a dense stand in up to 2 ft-. of water in. They can live in fresh or somewhat brackish water marshes and other wetlands. Cattails reproduce by both seed and vegetatively through clones emerging from a single rhizome. Rhizomes grow new shoots quickly, creating thick stands, great for covering many animals. A single rhizome may produce up to 100 stalks in a 10' diameter circle in a single growing season. Cattails provide important food source for both wildlife and people in a variety of ways. Muskrats uses the rhizomes for food and the foliage to build their homes. Cattails also provide a resting and nesting site for water birds like Mallards and geese.

 
yellow lily
Yellow lily flower or Spatterdock in the water

Tim Ervin

Spatterdock


Spatterdock can be a valuable plant for fish and wildlife habitat providing food, shelter, and a place of breeding for many. Submerged portions of all aquatic plants provide habitats for many micro and macro invertebrates

A perennial aquatic plant with a leaf blade of 6-12" long and about two-thirds as much across. Spatterdock is a large plant whose leaves are often floating, however submersed and emersed leaves are common.

Habitats include swamps, ponds, protected coves along lakes, and shallow areas along slow-moving rivers and blooms from spring to summer. Spatterdock provides shelter, shade, and cover for fish and aquatic wildlife.

Spatterdocks reproduce by using rhizome and seed dispersal and can form colonies in the right conditions. The aquatic plant thrives with full sunlight, still freshwater but, it can grow in a fair amount of shade. Spatterdocks provide food for deer to graze on, while beavers and muskrats consume the rhizomes. Also, the seeds are consumed by ducks and other waterfowl.

 
pickerel weed
Pickerelweed with butterfly on the flower

Tim Ervin

Pickerelweed


Pickerelweed is a native herbaceous emergent in the Pontederiaceae family. Found growing along shallow shorelines up to 4 feet tall. They are held well above the water for a showy long season display.

Pickerel weed can grow up from 2-4 ft tall and 18-24 in wide with narrow, heart-shaped, shiny jade green leaves, 10 in long. Flower spikes 6 in long, densely packed with tiny tubular blue flowers. Its preference is for freshwater depth up to 12 inches in full sun in rich loamy soils. It can tolerate part sun, poor soils, and occasional flooding up to 20 inches. The thick rhizomes spread to form large colonies. Flower spikes droop after bloom, releasing the distinctive seeds into the water.

The tall spikes of lavender-blue flowers last from summer through fall and attract many pollinators. This plant is resistant to browsing by deer and is tolerant of heat.

 
button bush
Button Bush with a butterfly on top

Tim Ervin

Buttonbush


Buttonbush is a deciduous shrub in the Rubiaceae (madder) family, it can grow as a tree up to 20 feet but is usually a small shrub up to 12 feet tall and 8 feet wide. In the summer, small, fragrant, white, tubular flowers occur in round clusters that have protruding styles, giving them a pincushion-like effect. The fruits are reddish-brown, showy, and persist into the winter. Native to East Canada, Central America, Cuba, much of the United States, and is found in all areas of North Carolina. This shrub needs consistently moist to wet, rich soils in full to partial sun. It does well in swamps, marshes, bogs, streambanks, riverbanks, lakes, and often in standing water up to 3 feet. It is adaptable to various soil types, except for dry ones, and is tolerant of heat and soil compaction. Flowering is poor in the shade or in dry soils.

The button bush attracts pollinators such as bees and butterflies with its sweet nectar while the seeds are eaten by birds. Each buttonbush fruit can produce up to 400 seeds. If you press on the button, it will break apart into its many individual seeds. Buttonbush provides food for wildlife including pollinators, birds such as waterfowls, and mammals. However, the plant contains tannins and the bitter glycosides; cephalanthin and cephaletin making it a poisonous plant. The leaves, especially when wilted, are toxic to domesticated animals.

 
wild rice
Wild Rice

Tim Ervin

Wild Rice


One of the amazing plant species in the Anacostia watershed is Wild Rice. Wild Rice (Zizania aquatica) is a type of grass that is native to North America. It is an annual plant that grows in a moist, aquatic habitat as the name suggests. The genus Zizania has 4 species, 3 of which are on this continent. Historically, Native Americans harvested the grain for hundreds of years. Although still abundant in the wild, we cultivate it in America for cereal and other sources of carbohydrates. Wild rice plants are about 3.3 to 10 ft tall and are topped with a large open flower cluster. While the cultivated North American species are both annual plants, the other two species are perennials. The ripened grains, dark brown to purplish black, are slender rods 0.4 to 0.8 in long. The U.S. species of wild rice plants can be found in Canada, parts of the Great Lakes, Texas, Florida, and the Gulf and Atlantic coasts. Wild rice grows in streams, river, or lakes. They prefer shallow water with a slow current and muddy substrate. Rice reproduces sexually, producing bisexual flowers that develop into fruits after pollination and fertilization. During reproduction, the stigma catches pollen from the stamens and conducts it down to the ovary, when it contacts with the ovule and fertilization occurs. Rice is self-fertile as fertilization occurs by the pollen of the same flower. The grain is the seed of the rice plant, a fertilized and ripened ovule containing a live embryo capable of germinating to produce a new plant. The grain of this grass is a food source for humans and animals alike. Birds are the main beneficiaries of the nutrient-rich grains in the wild. The grain is also eaten by dabbling ducks and other aquatic wildlife.

 
arrowhead
Arrowhead

Tim Ervin

Arrowhead


Arrowhead aquatic plant or duck-potato (Sagittaria latifolia) is a colony-forming plant usually found in shallow wetlands such as swamps, ditches, and slow streams. Arrowhead leaves are immersed. The petiole is triangular, erect, and can reach lengths anywhere from 5 to 50 cm. The leaf blade is sagittate (arrowhead in shape), measures up to 30 cm long, and up to 15 cm wide. If the plant is in a sunny location, it will always orient its leaves in a north-south direction. This behavior is to protect the leaves from the sun. Found in shallow water in lakes, ponds, tidal marshes, rivers, streams, and wetland margins. This common aquatic plant is native to, and found throughout Canada, U.S., Columbia, Ecuador, Venezuela, Central America, and Puerto Rico. Arrowhead aquatic plant can be propagated through rhizomes and arrowhead seeds. Following flowering, inconspicuous, small nut fruits develop. These contain only one winged seed each. Growing through seeds can be a long process since the seeds need two years to germinate. The arrowhead is not poisonous. In fact, the tubers found on the stolons of the plant are edible. The starch-rich tubers have a taste reminiscent of potatoes. You should peel them after preparation, however, because the skin contains many bitter substances. Not all species of arrowhead develop edible tubers, though. The tubers of arrowheads are prized foods by ducks, geese, muskrats, and nutria. Seeds are sometimes consumed by ducks. 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

 
swamp rose mallow
Swamp Rose Mallow Flowers

Tim Ervin

Swamp Rose Mallow


Swamp rose mallow is a large, beautiful addition to a rain garden or other wet areas of a landscape. The showy pink or white flowers with red centers attract pollinators, including hummingbirds, from midsummer to early fall.

The swamp rose mallow grows between 3 to 7 ft with a spread of 2 to 4 ft. The leaves of the plant are dark green on the top and white with hairs on the bottom, growing up to 8 inches. The leaves are oval or lanceolate shaped with slightly toothed edges and are lobe less or shallow lobed. The flowers of the plant bloom from July to September and can grow from 6 to 8 inches in diameter. The flowers are large and bell-shaped with five overlapping petals and a white or pink coloration. The inner portion of the flower is a dark crimson color with a staminal column protruding from the center. The staminal column has white anthers that surround a long style. After flowering, dark brown, kidney-shaped seeds are produced. The stems of the plant are rounded and green with tiny white hairs and a broad base.

The swamp rose mallow is grown in conditions that have moist to wet soil and primarily full sun. It is not affected by humidity and heat, so it is able to grow in these conditions particularly found in the deep south of the U.S. They are primarily found in areas that have swampy forests, wet meadows, or freshwater marshes from the southern to eastern portions of North America. They are also effective along streams and ponds. The swamp-rose mallow dies back in winter and re-sprouts in the spring. It reproduces via seeds or root division.

The swamp rose mallow is an important wildlife support plant particularly for pollinators and bird species. The nectar of the mallow is a source for species of butterflies such as the Eastern Tiger Swallowtail. The leaves and flowers of the plant also benefit caterpillars of multiple butterflies such as the Painted Lady. The seeds of the swamp rose mallow can be collected when they turn a dark brown coloration which occurs typically 4-5 weeks after flowering. The seeds are consumed by birds in the fall and winter. The plant has also been known to be deer resistant due to its mild taste.

 
beggerstick
Beggartick in bloom

Tim Ervin

Beggarticks


What are beggarticks? Common beggartick plants are members of the aster family, and the bright yellow flowers resemble daisies. You know how the stickery, fishhook-like seeds grab hold of whatever they touch, and you’ve probably spent hours picking the pesky things out of your socks or your dog’s coat. This handy little adaptation ensures that the plant spreads quickly when the sticky seeds catch a ride on an unsuspecting host. Leaves are compound in groups of 3 or 5. Leaflets are 2 to 4 inches long, ½ to 1 inch wide, on a slender stalk with the terminal leaflet predominant. Leaflets are lance shaped, tapered sharply at the tip and narrowing more abruptly at the base, sharply toothed around the edges, undersides with short soft hairs. Usually single, sometimes 2 or 3 stalked flower heads at the end of branching stems. Flowers are petal-less, have a yellow-orange center disk about ½ long to ¾ inch wide made up of tiny 5-lobed disk flowers. Flower stalks are slender and up to 6 inches long. Seed heads are round, larger than flower disks, covered in flat, dark brown seeds. Seeds are ¼ to 1/3 inch long with 2 barbed awns at the top that catch fur or fabric to disburse seeds. This plant can be found in moist woods, meadows, thickets, fields, roadsides, borders of streams, ponds, swamps, ditches and lakes. Bidens frondosa is native to Florida, North America. Their reproduction and colonization is effective pollination mechanisms and their distinctive dispersal adaptations. Seed distribution occurs by humans, animals, wind, and water. Beggarticks is a larval host for the Dainty Sulphur butterfly and a favorite nectar source for a myriad of butterflies. In Florida, it is the third most common source of nectar for honey production.

 
bald cyprus
Bald Cyprus in the pond

Tim Ervin

Bald Cypress


The bald cypress has reddish-brown to ashy gray bark that grows in wet soil with a strongly buttressed base. The wood of the bald cypress is valued for its water-resistance. It has horizontal roots that regularly send conical woody root projections called “knees” above the waterline. The Bald Cyprus is known for its “knees”, which aren’t human like. The technical term for the knee is pneumatophore, which means “air-bearing.” Growing up to 120 feet tall with a trunk 3-6 ft in diameter. The needle-like leaves are 1⁄2 to 3⁄4 inch long and are simple, alternate, green, and linear, with entire margins. In autumn, the leaves turn yellow or copper red. The bald cypress drops its needles each winter and then grows new leaves in the spring. The male catkins are about 2 mm in diameter and are borne in slender, purplish, drooping clusters 7 to 13 cm long. The cones turn from green to brownish-purple as they mature from October to December. The cones are 13 to 36 mm in diameter and consist of 9 to 15 four-sided scales that break away irregularly after maturity.

The bald cypress is a native tree to the southeastern United States that grows in the Mississippi Valley drainage basin, along the Gulf Coast, and up the coastal plain to the mid-Atlantic states. Bald cypresses are well-adapted to wet conditions along riverbanks and swamps. They can also be found in dry areas and sometimes planted as ornamental trees.

The bald cypress is monoecious. Male and female strobili mature in one growing season from buds formed the previous year. Pollen is shed in March and April. Female conelets are found singly or in clusters of two or three. Each scale can bear two irregular, triangular seeds with thick, horny, warty coats and projecting flanges. The number of seeds per cone averages 16 and ranges from 2 to 34. Bald cypress is one of the few conifer species that sprouts.

The seeds are eaten by wild turkey, wood ducks, evening grosbeak, water birds, and squirrels. The seeds that escape predation are dispersed by floodwaters.

Last updated: March 15, 2024

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