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Aquatic Vegetation Descriptions Proud to be central Indiana’s most chosen provider for lake and pond services.
Keep in Mind... Algae and aquatic weed growth cannot be prevented. Water, sunlight and nutrients guarantee aquatic vegetation. Products must be absorbed by actively growing algae or aquatic weeds. Most products remain active in the water for only a few minutes to a few hours.
Weed Species
Submersed & Emersed
Submersed weeds wilt and lose leaves 7-14 days after an application. Emersed weeds turn brown 5-10 days post application; cattails require 4-5 weeks. Weeds reproduce from seeds, fragmentation and underground root systems. Herbicides have no effect on seeds that can supply a fresh crop of plants for many years. During a season several different species of weeds will appear or regrow.
Algae Species Algae may change color 24-48 hours after an application and produce a musky odor. Allow 5-10 days for microbes to breakdown the treated algae. Water temperatures above 60 degrees and bright sunlight accelerate decomposition. Algae will return quickly, sometimes in just a couple days.
American Lotus Native Emersed Plant
American lotus is often confused with water lilies. Leaves are round, much larger (up to 2 feet in diameter), bluish-green in color and attached to the stem in center. Leaves are flat if floating or conical if emergent and can stand above the water as high as 3 1/2 feet.

Flowers are large (to 10 inches across) yellowish-white to yellow with more than 20 petals. The center of the flower, the seed structure, is cone-shaped (or like an inverted shower-head) and has openings in which the seeds develop. Lotus can form large colonies and spreads by seeds and large fleshy rhizomes.

Can be brought under control with several years of chemical control.
American Pondweed Native Submersed Plant
Commonly referred to as large leaf pondweed or broad-leaved pondweed. It produces a very slender, cylindrical, sometimes spotted stem up to four feet long. The leaves take two forms. Submersed leaves are 7" long and 2" wide and may be folded. Floating leaves are about 4-5" long and 1" wide and leathery in texture.

One plant can send out many leaves that float on the surface. Water beads off of the waxy cuticle of the leaf. Floating leaves provide shelter and habitat for fish.

If the plant reaches nuisance levels control can be achieved with aquatic herbicides.
Arrowhead Native Emersed Plant
One of about 30 species of similar looking plants with an arrowhead shaped leaf. Leaf has many uniform veins originating from the center and curving toward the margin. White, 3 petal flower arranged at the end of a thick stalk separate from the leaf.

Forms dense colonies on wet soil that become more open as the water deepens. Has a high affinity for rich phosphate soils and hard water. A favorite food for beavers and muskrats.

Control is effectively obtained through the use of contact aquatic herbicides.
Azolla NOT Native Emersed Plant
Mosquito Fern or Azolla is a small free-floating plant approximately 1 to 3/8 inches wide. Leaves overlap giving a quilted look to the surface and hide the stem. A single root protrudes from each stem. Mosquito ferns can vary in color from green to red and are generally found in quiet ponds protected from wind action.

They can be aggressive invaders and are often found mixed in with duckweeds or watermeal. If these fern colonies cover the surface of the water, then oxygen depletions and fish kills can occur. Mosquito fern has no known direct food value to wildlife.

Chemical control is recommended.
Bladderwort NOT Native Submersed Plant
Bladderwort is a submersed free-floating plant. There are approximately 200 species in the world, ranging in size from a few inches to several feet long. Tiny bladders attached to the leaves trap and digest very tiny animals. All bladderwort species are rootless. They have main stems from which lacy, often complex leaves grow. Bladderwort flowers are usually bright yellow (sometimes lavender, depending on species); the flowers have two 'lip-like' petals of about equal size. Flowers are on long stalks that emerge several inches above the water. The carnivorous bladders are attached at regular intervals along the linear leaf segments.
Blue-Green Native Algae Species
Cyanobacteria are extremely resistant to conventional chemical control methods. The mat forming species often appear greyish-green or brownish-blue in color. Mucus covering prevents environmental pressures and chemicals from damaging the cells.

Cyanobacteria can acquire nitrogen directly from the air if dissolved supplies run low. They can also store phosphorus for later use, enabling them to out compete other plants.

Disturbances from boating and spraying often release more patties from the bottom. Changes in weather and water chemistry tend to be help most in blue green reduction. Specialized products are available at additional cost but control cannot be guaranteed.
Brittle Naiad NOT Native Submersed Plant
Native to Europe this plant is now considered an invasive species in the US. The plant prefers calm waters and can grow in depths up to twelve feet. Thin rough leaves resemble plumes with small teeth on the edges curling downward.

Growing in dense clusters it has highly branched stems. Stems fragment easily and grow new plants. Seeds are also produced in large numbers. Plants form dense islands that choke out all other plants and limit water usage.

Control can be obtained with aquatic herbicides if nuisance levels are present.
Cabomba NOT Native Submersed Plant
Native to South America, this plant was introduced by the aquarium industry. It has a delicate appearance with leaves resembling fans, hence the nickname "fanwort". It has a small flower held above the water; ranging in color from pink to yellow-white. Plant color varies widely, from green leaves to reddish.

Plants will grow in depths of twelve feet provided sunlight is strong enough. Reproduction occurs from fragmentation and rhizomes, allowing for rapid spreading which forces out other desirable species. Waterways are choked out once this plant is present.

Control with aquatic herbicides produces good results.
Cattails Native Emersed Plant
Large plant growing 4 to 10 feet tall with leaf blades 1/2 to 1 inches wide. Female flower spike (seedhead) is tightly packed in the shape of a cigar; seedhead is rusty red-brown at maturity; male flower spike sits just above and is touching the female spike.

A marginal plant that may grow out to 4 feet of water. Plants lays dormant in winter, turning brown and dropping leaves, stalks and seeds into the water. Cattails turn open water into marshland and eventually dry land.

They can completely ring the shoreline of a pond in a few years if not controlled. Control is effectively obtained with the use of contact aquatic herbicides.
Chara Native Algae Species
Also known as muskgrass, or stonewort, this algae resembles a vascular plant. Found in hard water, chara gives the appearance of having leaves, stems and roots.

Plants can quickly grow 1-3' tall and develop a rough scaled coating of lime. Color varies from bright to burnt green or nearly white from hard water deposits. Chara is identifiable by its musky, skunk-like or garlic odor when crushed.

Mineral deposits on plants and hard water often require higher product rates. Chara is generally not a serious nuisance except in shallower bodies of water. Mature plants may leave mineral skeletons behind for several weeks after treatment.
Colorant NOT Native Colorant
Mainly used for aesthetics, aquatic colorant adds a colored tint to the water. A harmless blend of dyes that come in blue and mirror black varieties. Some unusual color outcomes can occur based on starting water color.

Some products advertise special dyes that filter out UV waves of sunlight. A reduction in sunlight can have an impact on plant growth in theory. Shallow water needs to be dyed very dark for adequate light reduction.

Rains can quickly wash out or dilute these pricey applications. Used as a supplement to a chemical control program can produce nice visual results.
Coontail Native Submersed Plant
Grows completely submerged, often floating in large clumps on the surface. Plant stems can reach nine feet in length, with rings of bright green leaves. The forked leaves are brittle and stiff to the touch resembling a wet raccoon's tail.

The plants have no roots at all, but sometimes develop modified root-like leaves that anchor the plant to the bottom. The plants sink to the bottom in the Fall then rise up in the Spring. Large masses of plants provided excellent fish spawning areas and produce large amounts of dissolved oxygen.

When nuisance levels are reached chemical control is effective.
Curlyleaf Pondweed NOT Native Submersed Plant
Very distinguishable with leaves 3-4" long that are ruffled or wavy. Originally from Eurasia, it thrives in US waters in conditions inhospitable to other plants. One of the first plants to arrive in the Spring it grows well in cold water.

Once present in a body of water they will quickly displace other native species and clog the water with their dense mass. Able to produce turions, a specialized seed, they can survive drought and freezing conditions for many seasons.

Chemical control is effective but once established many years of consistent treatment are often required to eliminate the invader.
Duckweed Native Emersed Plant
Simple plants lacking a stem or leaves with a small root dangling below the surface. About the size of rice they reproduce very quickly by budding. They will quickly cover the surface of quiet waters and often drift as the wind blows.

Spread easily between water bodies from transport by wildlife or water movement. Higher in protein than soybeans, they are eaten by humans and waterfowl. Its ability to cover the surface entirely provides shelter for fish fry, turtles and frogs.

Oxygen depletion often results when the surface is covered and sunlight blocked out. Early treatment is recommended. Effective duckweed control can be expensive.
Elodea Native Submersed Plant
Native Elodea is less robust than its aggressive invading cousin form South America. The aquarium industry introduced the Brazilian species that has become invasive.

Brazilian has small, strap-like leaves (1-inch long) in whorls of 3 to 6 around a thick stem. Native Elodea is smaller and typically has whorls of 3 leaves. Occasionally small white flowers with 3 petals on the frail stalk rise just above surface.

All species forms very dense mats reaching the surface and choking out other plants. If you observe Brazilian Elodea please take time to report its location. Long term professional chemical control is required to re-establish native species.
Eurasian Milfoil NOT Native Submersed Plant
This plant was introduces to the US from Asia, Europe and Africa in the 1950's. It has found a home in every State in the contiguous US. Able to reproduce from seed and fragmented pieces it is quick to fill a body of water.

Each leaf, composed of 24 leaflets that give it a feather appearance are whorled around a central stem. Stems are thick and green but can turn reddish. Plants can reach 10' tall and become topped-out with a small spiked flower above the water.

Dense mats reach the surface and choke out native species and entire waterways. Long term professional chemical control program is required to reestablish native species.
False Loosestrife Native Emersed Plant
False loosestrife can grow on shore and in waters up to 6' deep. On shore the plant has green leaves and lays flat on the mud or wet soil. In the water its limp stems with bronze or red leaves are held erect by the water. Leaves will become green as they break the surface of the water.

In late September thru October, tiny white flowers are connected directly to the stem. Bases of the stems are a favorite food for muskrats. It can resemble an underwater version of creeping water primrose.

Control can be obtained with correctly applied aquatic herbicides.
Filamentous Native Algae Species
This common species forms large green mats, islands and perimeter rings. Even the largest masses are composed of single cells grouped into filaments.

Color and appearance vary from cotton-like dark shades of green to bubbly bright green. It carpets the bottom of the water body and rises to the surface by trapping gases. This rapid ascent from the bottom is how water goes from clean to infested overnight.

Where water, nutrients and light are present algae will grow - it is not preventable. There are over 30,000 species of algae, each adapted to fill a niche. A consistent treatment program and quick response to growth are key to good control.
Floating Heart NOT Native Emersed Plant
Also known as Banana Lilly because of its banana shaped roots that store nutrients. Varieties are numerous, producing yellow or white flowers. Leaves are small and resemble a heart with a notch where the stem attaches. It is often mistaken for a miniature water lily.

It grows rooted or as a floating plant and can quickly fill a pond in a couple seasons. Leaves are green above the water and a dull purple below.

Due to its high rate of growth and invasive habits it is VERY difficult to control. Plan on a long term program for control.
General Weeds Native Emersed Plant
These are a variety of weeds, generally terrestrial, that grow in the stone around ponds or the shoreline detracting from the appearance.

Due to the proximity of the plants to the water, aquatic herbicides need to be used and applied by one of our licensed aquatic applicators.

Usually weeds are dead or dying within seven days of an application.
Horned Pondweed Native Submersed Plant
Long, linear, threadlike leaves are mostly opposite on slender branching stems. Leaf tip tapers to a point. The seeds occur in groups of 2 to 4 forming at the leaf axils and are shaped like horns, hence the name. Found in shallower depths, they can thrive in fresh or brackish waters.

One of the first plants to appear in the Spring, it does best in cool water. When the water warms in June they release seeds and die back. Often the plants will return in the Fall. Seeds can germinate in the same season.

Chemical control can be achieved effectively if nuisance levels are reached.
Hydrilla NOT Native Submersed Plant
The most feared invasive weed species to enter the United States and recently Indiana. Introduced as an aquarium plant from the warm waters of Asia, Europe and Africa. Able to lay dormant in sediment for several years it is the greatest threat to US waterways.

Small, strap-like leaves (1-inch long) in whorls of 3 to 8 around stem.

Leaf margins are serrated and rough to the touch; sometimes 2 to 4 small barbs or spines on underside midrib of leaf. Resembles Elodea and Egeria which are smooth to the touch.

Forms very dense mats reaching the surface and choking out native species.

Please report this plant so a long term chemical control program can be designed.
Northern Milfoil Native Submersed Plant
A native plant, it grows in depths of up to 20 feet. Dark Green feathery leaves are grouped in fours around a hollow stem that is usually pinkish in color. Will raise a 3-4 inch reddish flowering spike above the surface.

Often mistaken for coontail or Eurasian milfoil, it doesn't branch at the surface as much as Eurasian, has half as many leaflet pairs as Eurasian and the leaves of Northern are rigid out of the water; Eurasian leaves are limp. Can quickly overtake a waterway.

An excellent habitat plant for aquatic life, it reproduces from seeds, buds and fragmentation. Chemical control is necessary once established.
Parrot Feather NOT Native Emersed Plant
Native to the Amazon River it can now be found worldwide. No male plants are found outside South America. Only female plants are found in the US. It reproduces by fragmentation or through root systems.

Erect green stem with whorled leaves resemble a feather. Rooted along shoreline and stems trail along the ground or float across the water surface, becoming erect at the leafy end. Can form a tangled mass of floating stems that crowds out all other vegetation.

Herbicide control is difficult because of a protective waxy cuticle and physical removal results in further growth.
Phragmites NOT Native Emersed Plant
A large grass that forms extensive stands, growing up to 19' tall and spreading at a rate of 16' per year. It can grow in damp ground, 3' deep water or even as a floating mat. It can tolerate brackish water and alkaline conditions.

It is believed there is a native species but it has been out competed by the invasive European and Asian varieties. Phragmites are home to numerous birds and wildlife.

Unfortunately they crowd out all native plants by releasing an acid as they are degraded by light. This acid hits other seeds and plants with a toxin preventing growth.

A professional herbicide management program is suggested for control.
Pickerel Weed Native Emersed Plant
Found in shallow waters and wet soils this plant grows in thick clumps. Large waxy leaves and a large stalk of purple flowers in the Summer make this a popular water garden plant. Fibrous roots give rise to rhizomes that allow rapid spreading.

Insects and waterfowl make use of the flowers and fruit of the plant. Often used as biological filters in polluted waters. Can become invasive under the right conditions.

Control with proper aquatic herbicides can be achieved.
Planktonic Native Algae Species
Planktonic algae are microscopic free-floating cells suspended in the water column. This population of cells is generally composed of green and blue-green alga. Water discoloration from green to brown commonly occurs from free floating cells.

Severe blooms create a rust red, green or brown paint-like film on the water. Densities can fluctuate from a minor dusting to a pea soup several feet thick.

Control can be obtained on most species but safety factors should be weighed. The large volume of water occupied by cells can impact dissolved oxygen levels. Potential for a fish kill is increased when these cells die off suddenly from natural causes.
Pre Emergent NOT Native Submersed Plant
Pre Emergent application or submersed Weeds. Plants have not yet become visible but are known to become a nuisance.
Purple Loosestrife NOT Native Emersed Plant
Introduced to the US as a garden plant this species has become very invasive. Growing to heights of six feet a single plant can produce a colony 6' in diameter. Flowers are reddish purple and clustered tightly. When the seeds are mature in the Fall the leaves often turn bright red. A single plant will produce 3 million seeds annually.

The plant can also reproduce from fragmentation.

Infestations result in elimination of all native species and clogging of waterways. Once established physical and chemical control is difficult and expensive.

If you observe this plant growing please take the time to report its location.
Rip Rap Native Emersed Plant
Rock area around shoreline perimeter.
Rushes Native Emersed Plant
A large number of grass-like species fall into this plant category. Able to grow in a variety of aquatic conditions they form large colonies. Rushes are often seen as tall, leafless stems. Stems can be round, triangular or blade-like.

Ducks and other wildlife use rushes as a food source. Seeds or flowers are found on the stem tips, usually in clumps. Plants can range from a few inches tall to 10'.

Numerous benefits for aquatic life and tends to stay compact and dense. Chemical control methods are effective when necessary.
Sago Pondweed Native Submersed Plant
This plant grows on every continent except Antarctica. It is fully submerged and does not have any floating or emerged leaves. Leaves are filament-like. The flowers are wind pollinated and the seeds float. Tubers form on the rhizomes and are rich in starch. Reproduction occurs from seeds, rhizomes or fragmentation.

The whole plant provides food for a diverse population of wildlife. Waterfowl eat both the fruits and tubers. Plants rapidly spreads between bodies of water and can become a nuisance in smaller water bodies.

Chemical control is effective if treatment is required.
Sandbar Willow Native Emersed Plant
A medium native suckering shrub 3-20' tall found along riverbanks and water bodies. Prefers sandy soils, will aggressively spread from originating site. Looks very similar to willow trees but tends to be more upright and sparse.

Will develop into large colonies and crowd out other plants. Deer will eat the leaves and nesting birds use the numerous branches for shelter. Their root systems increase water leaking potential and create high evaporation rates.

Chemical control is effective if growth reaches nuisance levels. After a treatment the woody branches and trunk remain intact.
Slender Spike Rush Native Emersed Plant
Slender spike rush can grow completely underwater and appear as a submerged plant Spike rushes can grow in shallow water or moist soils and grow from rhizomes. Stems are unbranched with sheaths around the base but can be round, square, or flattened depending on the species. All spike rushes have small fruiting spikes at the tips of the stem. 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. Very difficult to control when submersed.
Southern Naiad Native Submersed Plant
There are about 40 species of naiads in the world. The stems are very long and have many branches. Leaves are deep green to purplish green and very narrow and short. Reproduction occurs from seed and fragmentation of the brittle branches.

Naiads prefers warmer water and grow at an astounding rate. Plants can bloom into giant bushes and even after treatment reappear several times in a season. Spreads like wildfire in the warm months.

Chemical control is effective but this plant can return fairly quickly after treatment.
Spatterdock Native Emersed Plant
A rooted, floating-leaved plant with a bright yellow flower sphere. In early spring the leaves are below the surface. By late spring the broad, dark green, heart-shaped leaves are floating or standing above the water. Horizontal roots can be six inches thick and several feet long, resembling palm tree trunks.

Reproduction occurs from seed, root growth and fragmented roots. Provided the plant does not reach nuisance levels it has many benefits. Leaves shelter aquatic life and roots feed beaver and muskrats. Seeds and roots are also used for human consumption.

These plants can spread rapidly and chemical control can be expensive.
Spike Needle Rush Native Emersed Plant
There are many species of spike rush and they are difficult to differentiate. In general they are small plants often confused with grasses or sedges. They can grow completely underwater and appear as a submerged plant or grow emersed in moist soils.

They grow and spread primarily through rhizomes. Stems are unbranched. All spike rushes have small fruiting spikes at the tips of their stems. Shoreline plants look like bright green grass. Often the submerged plants will be pulled out of the bottom sediment and float to the top like grass clippings with a white root.

Emersed plants are controlled effectively if needed. Submerged plants can be difficult.
Spyrogyra Native Algae Species
Forms extensive floating mats that are usually very bright green. Filaments are very slippery to the touch when the algae is removed from the water. Most abundant in early spring and usually dissipates by mid-summer, likes colder water.

Takes advantage of cooler water to grow quickly. Contains bubbles from trapped gases. Even the largest masses are composed of single cells grouped into filaments.

Where water, nutrients and light are present algae will grow - it is not preventable. There are over 30,000 species of algae, each adapted to fill a niche. A consistent treatment program and quick response to growth are key to good control.
Variable Leaf Milfoil NOT Native Submersed Plant
Water Lilies Native Emersed Plant
The water lily is a perennial plant that often forms dense colonies. Leaves usually float on the surface rising on flexible stalks from large rhizomes. More round than heart-shaped, the leaves are bright green, 6 to 12 inches in diameter with a slit about 1/3 the length of the leaf.

Flowers are on separate stalks and may float or stick above the water. Spreading occurs from seeds or rhizomes. Very aggressive spreading plant once established. Will take over in depths less than 7'.

Can be brought under control with several years of chemical control.
Water Plantain Native Emersed Plant
A wetland plant that prefers to grow in moist soils or shoreline shallows. It has a thick stalk with a leaf that is lance-shaped or resembles a candle flame. When the leaves are submerged they are more ribbon-like.

White or pale purple, 3-petal flowers are at the end of a thick stalk separate from the leaf. Flowering from June - August the plant varies from 1-3 feet in height.

Once introduced water plantain can spread rapidly along the shoreline.

Control with aquatic herbicides can be achieved when necessary. Multiple seasons are required for established colonies as seeds continue to germinate.
Water Primrose NOT Native Emersed Plant
From South America this invasive plant stands erect along the shoreline and forms long runners (up to 16 feet) that creep across wet soil or float across the water surface. Vine-like runners can rise 1-2' above the surface and form roots that hang below the water.

Leaves can be green or reddish, willow-like on the erect stems to round or oval on the floating stems. In the summer months it blooms with a yellow flower.

Able to double its mass every 15 days and reproduce from fragmentation, roots and seed make this a highly invasive plant. Control is best during summer when the leaf mass above water is sufficient for maximum herbicide uptake.
Water Stargrass Native Submersed Plant
Grass-like in appearance with thin branching dark-green stems and alternate leaves with no prominent mid vein. It can grow up to 8 feet long and form floating islands. Flowers rise above the surface and are bright yellow, star-shaped, with 6 narrow petals. Flowers bloom in the morning and wilt in the evening.

Water stargrass reproduces from seeds and through fragmentation, preferring hard, alkaline waters. Leaves will often collect water deposits giving them a gritty texture.

Control with aquatic herbicides is best achieved on young plants before deposits build up on the leaves reducing herbicide uptake.
Water Willow Native Emersed Plant
A very hardy and quick spreading plant found in both slow and fast moving waters. It resembles willow tree branches stuck in wet soil. Growing to a height of 2-3', it can grow in water up to 3 feet deep.

Creeping rhizomes send out runners, creating a quick colony of plants. Small light lavender to white flowers are produced May thru October. Provides spawning sites and shelter for many aquatic species.

Aquatic herbicides are effective when the plant reaches nuisance levels. Often more than one season of treatment is required for control.
Watermeal Native Emersed Plant
Watermeals are the smallest flowering plants in the world. They are a very tiny (less than 1 millimeter) light green free-floating, rootless plant. Watermeal tends to grow in dense colonies in quiet water, undisturbed by wave action. Watermeal can be an aggressive invader of ponds and are often found mixed in with duckweeds.

If colonies cover the surface of the water, then oxygen depletion and fish kills can occur. These plants should be controlled before they cover the entire surface of the pond.

Control can be expensive as normally the entire volume of water needs to be treated. Control attempts often fail due to the resistant nature of the plant.
Watershield Native Emersed Plant
Watershield is a perennial plant with relatively small, floating oval to elliptical leaves (less than 5 inches in diameter) with no slit. Watershield has a distinctive gelatinous slime on the underside of the leaves and coating the stems.

Leaves are green above while the underside and stems are reddish-purple. Stems attach at the center of the leaves. Flowers are small and dull-reddish in color.

Watershield tends to be found in soft, acidic waters and can form large invasive colonies. Control with aquatic herbicides is recommended to prevent spreading.