Florida is home to hundreds of native – and invasive – aquatic plants that live among its waterbodies. And with freshwater, brackish water and saltwater spread among lakes, ponds, marshes, wetlands, streams, springs and much, much more, there is a lot of variety when it comes to aquatic plants in Florida.
We will walk through several varieties of native and invasive as well as emergent and submerged aquatic plants, all of which are commonly found in Florida. Learn more about what aquatic plants are in Clarke’s guide, or check out aquatic plants in other regions, such as Virginia.
Tape Grass or Vallisnerai American is a submersed (fully underwater) aquatic plant found throughout many clean, clear Florida lakes, rivers and natural springs. It creates underwater meadows for fish, turtles and more to feast on.
Appearance: Tape grass looks how it sounds – like long, thicker blades of grass growing underwater. Its individual blades are about an inch wide and can grow to be several feet long with round tips and raised ‘veins’ running its length. In shallower waters, it often ‘bends’ to meet the current, earning it the nickname of ‘eel grass’.
Watch Out: As tape grass grows vertically and quite long, it can sometimes become a swimming and recreational use hazard – or at least alarm swimmers whose legs get tangled!
How to Control Tape Grass: Tape grass can be controlled using aquatic herbicides or by dyeing the waterbody – this blocks out some of the sunlight and helps limit plant growth.
What is Sago Pondweed?
Sago Pondweed or Stuckenia Pectinata is another submersed aquatic grass, this time growing in shallower waters (both fresh and brackish) that tend to be stagnant and slow-moving. In Florida, it can be found in ponds, marshes and spring-fed rivers.
Appearance: Sago pondweed’s stems are about an eighth of an inch thick and very flexible – they grow to be several feet long with long, narrow tapered leaves protruding from them. Its stems have many branches that usually have a base color of green, tinged with browns and reds. It also has tiny, spikey flowers that are greenish with several whorls.
A Good Food Source: Sago Pondweed is usually a great plant to have in a lake or pond. It contains an ample amount of nutritious food sources for fish, birds, waterfowl and more thanks to its tubers, seeds, leaves, stems and roots.
How to Control Sago Pondweed: While you can try to manually rake out Sago Pondweed, it is very likely to re-establish thanks to its many ribosomes, roots and seeds. Instead, to control this plant, you could try the proper herbicide (have a professional recommend and apply this for the safest, most efficient results) or stocking the water with grass carp to feed upon it.
What is Duck Potato?
Duck Potato or Sagittaria Lancifolia gets its name from the large, tuber-shaped, underground stems. Duck Potato can be found growing in the swamps, ditches, lakes and streams of Florida.
Appearance: Duck Potato grows from the bottom layer of the water body to about three feet above the surface. It has long-petiole leaves that are arrow-shaped and small clusters of flowers with three petals.
Nutritious: Duck Potato’s starchy tubers aren’t just eaten by waterfowl and muskrats, they were also once a source of nutrition for Native Americans, who called it ‘Wapato’.
How to Control Duck Potato: For the most part, Duck Potato is helpful for nutrient absorption, erosion control and aquatic habitats and don’t need to be removed. But in the case that your aquatic manager recommends doing so, its numerous tubers, seeds and stems, make it difficult to manually remove the plant. Instead, opt for an herbicide or seek ways to move and aerate the water – which will discourage growth.
What is Small Duckweed?
Small Duckweed or Lemna Valdiviana consists of thin roots with a single small leaf floating on the surface. They are found in still, sluggish water in large floating mat formations.
Appearance: Small Duckweed consists of floating, oval-shaped leaves anchored by a single root and clustered together. They are about 0.1 inches long and 0.05 inches wide in a light green color.
Native?: While Small Duckweed is native to Florida, it can grow quickly and aggressively, covering the surface of a waterbody. This results in oxygen depletion, fish kills, and more negative effects if left unchecked.
How to Control Small Duckweed: When it comes to this Floridian aquatic plant, there are quite a few options. Adding fish such as koi or goldfish to eat the plants where reasonable, aerating the water to discourage new growth, and using the proper chemicals appropriately are all options.
What is Soft-Stem Bulrush?
Soft-Stem Bulrush or Scirpus Validus is a grass like plant with triangular stems – known as a sedge –topped by a cluster of flowers that hangs down. It grows in marshes, ponds and streams.
Appearance: Soft-Stem Bulrush look like large, triangular blades of grass with no branches and a topping of fluffy brown flowers. They grow to be about eight feet tall and are often found in large colonies on shorelines and in shallow waters.
Restorative: Soft-Stem Bulrush helps stabilize and restore wetlands and marshes as well as aids erosion control – thus, it is often included in Restoration and Stormwater Management Projects.
How to Control Soft-Stem Bulrush: To help curb out-of-control cases, you will want to opt for an herbicide applied later in the season when seed heads appear and can be treated simultaneously. Otherwise, its seeds will likely re-grow.
What is Pickerel Weed?
Pickerel Weed or Pontederia cordata is a native Floridian plant marked by vibrant purple flowers atop bright green stalks and sheaths. It can be found in and around the shores of slow waters, such as marshes, canals and swamps, growing in large colonies and spreading via underground rhizome systems. It is mainly found in South Florida.
Appearance: Pickerel Weed is a medium-sized aquatic plant, which reaches about two to four feet in height. It has long, narrow leaves that can vary in size and shape, but is distinguished by a crowning, half-foot spike covered in hundreds of small, purple and blue flowers.
Hyper-Local: While Pickerel Weed is found in nearly every county within Florida, it’s also found in eastern and central North America, as well as Mexico, the Caribbean, and South America. Pickerel Weed is also considered an invasive pest in South Africa where it crowds out native plants.
How to Control Pickerel Weed: While Pickerel Weed doesn’t usually require much management due to its numerous benefits for erosion control, nutrient absorption and more, the primary management option for this aquatic plant is via herbicides.
INVASIVE AQUATIC PLANTS IN FLORIDA
What is Crested Floating Heart?
Crested Floating Heart or Nymphoides Cristata is found floating in freshwater. It usually has runners that are rooted in the ground layer of the waterbody but can occasionally be found free-floating when the roots become unearthed.
Appearance: Crested Floating Heart consists of large, flat, floating, heart-shaped leaves with purple bottoms. They are anchored by roots and topped with white flowers with yellow buds.
Restorative: Crested Floating Heart is an invasive species, originally brought to the United States for ornamental purposes. It grows quickly, covering surfaces, depleting oxygen and crowding out other plants. It usually spreads via the movement of boats and anchors.
How to Control Crested Floating Heart: Try to control or prevent the spread of this invasive species by making sure boats entering the waterbody are clean, dry, and drained. While most physical methods of removal only serve to further spread its numerous ribosomes and seeds, select herbicides have shown some promise in treating this plant.
What is Hydrilla?
Hydrilla or Hydrilla Verticillata is a fully submerged, perennial aquatic plant species that is infamous for being one of the most pervasive invasive plants. In fact, Hydrilla has made its way into nearly every type of freshwater, including rivers, lakes, streams, ponds, canals, ditches, reservoirs and more.
Appearance: Hydrilla consists of thicker stems covered in small, bright-green leaves that come to a point with serrated edges. It also has what is best described as a sharp tooth under the center of each leaf. These leaves are arranged in whorls of about five leaves directly attached to the stem. At the end of each stem, which can reach up to thirty feet, is a tuber. Hydrilla is usually found in vast quantities, forming thick mats. It can survive both embedded in the ground as well as free-floating.
Named for Hydra: Part of what makes Hydrilla so tricky is its capability to grow a new plant from just a small stem piece – similar to the mythical nine-headed serpent in Greek mythology.
How to Control Hydrilla: There are a lot of options when it comes to controlling Hydrilla, but few of them are successful – physical raking and suction harvesting, biological controls such as tuber-feeding weevils and grass carp as well as chemical herbicides. An aquatic plant management company such as Clarke will have successful experience with this type of work.
What is Water Lettuce?
Water Lettuce or Pistia stratiotes was first reported in Florida in 1765, although experts disagree as to whether it is native to the United States. Water Lettuce is a free-floating, emergent aquatic plant that closely resembles a head of lettuce cut in half.
Appearance: As mentioned, Water Lettuce resembles a light green head of actual lettuce, with thick, velvety leaves that are rounded and ridged at their ends. It also has small white to pale green flowers and feathery roots dangling underneath it further into the water.
An Aggressive Invasive: Water Lettuce is a perennial plant, which lends itself to creating thick, semi-permanent mats that block off sunlight and decrease dissolved oxygen levels. This not only lowers water quality but inhibits the growth of submerged plants, recreation and wildlife.
How to Control Water Lettuce: Water Lettuce should be controlled to ensure that it does not cover or inhibit pond or canal surfaces and drains. This can be done via raking, skimming, or approved herbicides applied by a professional.
Looking for Management of Your Waterbody’s Aquatic Plants?
Our experts at Clarke have years of experience working with a vast variety of lakes, ponds, stormwater ponds and more throughout the United States, with a focus on catering to their unique needs and goals and an emphasis on using science-based techniques and technologies to do so. For a free assessment or any questions regarding your waterbody’s quality, contact our team here. To learn more about our aquatic plant management capabilities in Florida, click here.