Algae and Plant I.D. Guide

Microscopic algae is usually suspended at the top of the water column. This bloom can vary in color, most commonly the bloom is a pea soup green and can also have brown variations. These tiny plants get their nutrients directly from the water, so their growth and reproduction are dependent on the amount of nutrients present. Ponds collect nutrient-loaded water flowing from yards, roads, and fields as a result they often grow an abundance of planktonic algae. 

Also known as Water Silk, it is best recognized as long, thick, green, and slimy. Its name comes from its chloroplast being helical or in spiral form. Filamentous algae floats to the surface forming large mats. There are many species of filamentous algae and often more than one species will be present at the same time in the pond. The algae blooms can start as early as spring but are maintained with high temperatures through the summer and fall months. 

Also known as cotton algae or horsehair algae. The colors can vary but often are in variations of green and yellow. The surface mats generally form in warmer weather when gas bubbles produced by the plant are trapped within the dense growth causing them to become buoyant. Disturbance of these mats by high wind or heavy rain events may cause them to temporarily sink. This often gives an impression that the growth has disappeared yet returns to the surface within a short period of time. 

Harmful fresh and brackish water bloom that contains hepatotoxins and neurotoxins. Can vary in color but mostly in variations of green suspended on the surface of the water. This bloom typically thrives in warm slow-moving water. The blooms with the highest biomass occur in waters that are high in nitrogen or phosphorus. Microcystis also require enough light intensity to conduct photosynthesis, which results in blooms. 

The microscopic protozoan can be found in freshwater and saltwater environments. It can be best identified by its red color on the surface of the pond. Euglena is tough to manage because it is a single-cell organism covered by a protein pellicle. Euglena also releases granules from its center that form an even harder shell to protect it when necessary from sun damage. This produces that bright red color. Euglena is most commonly found in warm stagnant water in the heat of the summer.  

Also known as Floating Clover. Ovular floating clovers with extended roots on the underside of the plant. The clovers are green in color to yellow in color and can have a reddish underside. Duckweed grows quickly produces new offshoots rapidly and can cover a pond for a few days. Duckweed reproduction is asexual and by budding and fragmentation. 

Also known as spatterdock this plant prefers muck or silty shallow areas. Leaves are large and heart shaped usually 8-16 inches long. The flower s bright yellow with single petals. Flowers bloom from May to October, partially opening in the morning and closing early afternoon or night.  Spreads horizontally from a thick rhizome. The flower gives way to seeds that open upon ripening. These seeds are spread over the surface of the water. Flowers and leaf stems die back to the rhizome in autumn.   This plant can inhabit ponds, lakes and rivers.  

Also known as marsh pennywort and dollarweed. Leaves have round large lobes about the size of a half dollar with a white center connecting to the stalk. The Stalks extend horizontally off a buried horizontal root system. The stalks are attached centrally to the leaf. This plant is beneficial in algae control by shading out the shallow water that it inhabits. This plant can grow in any moist soil along shorelines.  

Also known as Fringed water lily.  Leaves are heart-shaped and arranged opposite on the stem. The flower is yellow with five petals. The leaves float at surface level, herbicides are easily washed off with any water movement near the plants. These plants reproduce by fragmentation and seeds. The seeds have seed hairs which allow the plant to migrate in flowing streams and rivers and populate a vast majority of pre-inhabited waters.   

It has narrow thread-like leaves alternately arranged on a stem up to six inches in length with strong veins. Once mature, there is a simple compressed stem near the base and branches abundantly near the top. The stem emerges from the water with seeds closely resembling nutlike beads. The plant reaches a maximum height of three feet in height. Sago pondweed can be found in alkaline, brackish, or saline water of ponds, rivers, marshes, and ocean shores. 

Also known as Crisp pondweed. Leaves are all submersed and alternate with no leaf stalks. Leaves are very easy to identify by the wavy edges on the margin of the leaf. The flowering parts are greenish brown with greenish-red sepals. The plant produces three to four achenes per flower. Reproduces by germination of seeds in the fall. The plant varies in height depending on the time of year. This plant is most abundant in lakes and ponds tolerant of slightly brackish as well as fresh water.  

Also known as Long-Leaf pondweed. It has long sword-shaped leaves that float on the water's surface. Leaves are arranged opposite on the stem. Leaves are often green to pale yellow. The stem is two to eight inches long compressed and glabrous. Produces a floral spike reddish brown. This spike contains multiple seeds that have a keel shape. American pondweed prefers full sun, warm standing water up to four feet deep, and a mucky bottom. This plant can spread aggressively in shallow water. 

Also known as Grassy pondweed. Submersed leaves are reddish green and alternate in venation. Floating Leaves are elliptical and have veins running down the center of the leaf.  The stem is cylindrical with several branches. The branches are finely toothy with a white mid-rib. The flowers are spikes that are just below the water's surface with a thick stemming penducile. This plant prefers shallow water ponds and lakes but can also grow in ditches, swamps, and bogs.  

Also known as Water Nymph or Guppy grass. Very Leafy plant, leaves are wider at the base and arranged in whorls or of three on the plant stem. The seed is on the axis leaf. The stem can get to about three feet in length and appear transparent.  The plant remains submerged throughout its lifespan. They are commonly found in fresh and brackish water, lakes, springs, canals, streams, and ponds. 

Also known as Wild Celery or Tape grass. Leaves are long and ribbon like with sharp veins along the whole leaf. Plant can reach a height of three feet. Ealgrass reproduces sexually and and asexually when the female flowers are fertilized by drifting pollen and develop into seed-bearing shoots. The shoots eventually break off, float to the surface and release their seeds. Eelgrass beds are completely submerged. Can be present in sandy or muddy bottoms up to fifteen feet in depth.

Leaves in whorls of four, with 14 to 20 pairs of leave divisions. The stalk is reddish in color and produces small pink flower spikes up to four inches long bearing tiny yellow flowers. Male and female flowers are found on the same plant. Approximately 100 seeds are produced each season, however, can reproduce asexually by fragmentation. This plant can grow in variable depths up to 10 feet. The preferred habitat is shallow water in lakes, ponds, and streams.

Also known as Swollen bladderwort. Bladdwort is a carnivorous free floating plant without visbal roots . The leaves are finely divided and scatterd along the stem. There are several bladder like apppendages along the leaves to help trap small aquatic invertebrates for consumption. When mature, it produces a small yellow flower above the surface. Bladderwort thrives in several habitats includinging marshes, rivers, streams, ponds and lakes.

Also known as Common waterweed. This plant has broad oval leaves usually four in number arranged in a whorl around the stem. The whorls are compact near growth time but are spaced out further down the stem. Leaves are smooth in the margin and tend to have a slight curl. This is one of the only aquatic plants that can remain green all winter long. Reproduction is primarily through fragmentation. This plant can survive in most waterways along with lakes and ponds.

Also known as Floating Primrose Willow. It grows horizontally along the shoreline and has shoots that can reach up to 16 ft in length. The leaves are green with a red vein. Stems are deep red, hollow and are alternate along the shoot. Produces a yellow flower with five petals that is located at the end of the shoot. The petals are replaced by cylindrical seed capsules. Each seed capsule has five narrow cells, and each cell contains a row of seeds. Primrose primarily grows in muddy soils along shorelines.

Tall grass that can grow up to 18 feet tall. Leaves are long and elliptical and opposite in venation. Phragmites bloom with purple to gold highly branched panicles of flowers. The seeds are grayish and appear fluffy due to the silky hairs that cover each seed. Dispersal occurs through rhizomes, stolons, and seeds. Stolons can grow up to 43 feet from the parent plant. Stems are hollow, usually green with yellow nodes during the growing season, and yellow when dormant in the winter. The roots grow parallel to the ground and can have multiple stems of one root system. The plants inhabit fresh to slightly brackish waters and are considered aquatic or semi-aquatic covering shorelines and ditches

Also known as Woodrush and Club Rush. This plant produces three stems that are long and triangular. The stems can have flat leaves but most do not. Bullrush has clusters of brown flowers with one seed that does not open when ripe and are located on the end of the stem. Inhabits shallow water shorelines and wetlands

Also known as Spike Loosestrife. Plants are two to seven feet in height. The stems are haired and are four-sided. Leaves are lance-shaped with smooth edges and grow up to four inches long. They are usually arranged in pairs opposite each other on the stem. Individual flowers have five or six pink-purple petals surrounding small, yellow centers. Single flowers make up flower spikes, which can be up to one foot tall. Flowers bloom from early July through September. Purple Loosestrife inhabits shallow wetlands and shorelines.

Also known as Pickerel Rush. This plant produces heart-shaped leaves with curving veins parallel to the margin. The flowers are one long spike, six inches in length at the end of the stem, purple or violet in color. Plants can grow up to four feet in height. Seeds are produced on a seed head and are dispersed when the plant starts to go dormant for winter. This plant inhabits shallow water along silted shorelines. Pickerelweed can be a great filter for sediment and nutrients entering the ponds from runoff