Introduction
Cattails (Typha spp.) are wetland plants with long, erect leaves that can grow over 10 feet tall. They are common sights in marshes, swamps, ditches, and the edges of ponds and lakes across North America.
While providing important habitat and other ecological benefits, cattails are considered a nuisance plant when they spread aggressively and crowd out other native species. Their rapid growth allows them to quickly dominate wet areas, altering ecosystems and reducing biodiversity.
Cattails spread rapidly through rhizomes and form dense stands that can clog waterways, damage infrastructure, and reduce recreational and aesthetic value of water bodies. Their ability to thrive and take over wet areas is what makes cattails a nuisance plant for many property owners and land managers.
Rapid Growth
One of the main reasons cattails are considered a nuisance is due to their extremely rapid growth rate, allowing them to quickly invade and take over areas. Cattails primarily spread through their underground rhizome root systems, which can expand outward by several feet per year from the parent plant (https://www.thespruce.com/growing-common-cattail-plants-5088737). The rhizomes continuously sprout up new shoots, creating dense clusters. Cattails also spread readily by seed dispersal. Each mature cattail can produce hundreds of thousands of tiny seeds that are easily spread by wind or water (https://somethingscrawlinginmyhair.com/2020/08/09/lets-see-how-fast-cattails-grow/). These seeds germinate readily in muddy soil. With their dual reproductive strategies, cattails are able to achieve incredibly fast growth rates. They can completely take over portions of wetlands, ditches, ponds and lakes in just a few years if left uncontrolled.
Crowd Out Native Species
One of the main issues with invasive cattails like narrow-leaved cattail (Typha angustifolia) and hybrid cattail (Typha x glauca) is that they can rapidly crowd out and displace native wetland plant species (Hawaii Invasive Species Council | Cattail, n.d.). These aggressive invaders form dense monoculture stands that take over marshes and wetlands, displacing diverse native vegetation.
This is detrimental because many native wetland plants provide important food and habitat for wildlife. For example, native sedges, rushes, and grasses are beneficial for nesting waterfowl and migratory birds. Diverse native wetland plants also support populations of frogs, turtles, dragonflies and other wildlife that rely on wetlands for breeding and shelter. When invasive cattails take over, they reduce plant diversity and the quality of food and habitat available to wildlife in wetlands.
Alter Ecosystems
Large stands of cattails can significantly alter wetland ecosystems in various ways. As a highly competitive plant, cattails can crowd out native wetland vegetation and reduce biodiversity. According to the U.S. Geological Survey, dense cattail stands change wetland hydrology by slowing water flow. This allows sediment and pollutants to accumulate, degrading water quality. Cattails also alter biogeochemical cycling of nutrients like nitrogen and carbon. As cattail debris decomposes, it releases nutrients that stimulate further cattail growth. This creates a feedback loop that enables cattails to exponentially spread. By changing water flow, nutrient cycles, and decreasing biodiversity, invasive cattail stands profoundly alter delicate wetland ecosystems.
Reduce Biodiversity
One of the biggest problems caused by invasive cattails is their ability to form dense monocultures that crowd out native plant species and reduce biodiversity. Cattail stands expand rapidly via rhizomes, forming single-species colonies that completely dominate wetlands.
According to the U.S. Geological Survey, invasion of cattails has been “particularly detrimental to native floral and faunal biodiversity around the Laurentian Great Lakes.” https://www.usgs.gov/news/cattail-typha-invasion-north-american-wetlands
The dense mat of cattail leaves shades out light needed by other submerged and emergent aquatic plants. The lack of plant diversity and habitat complexity reduces resources available to wildlife. Native fish, birds, amphibians, and insects are impacted when cattails replace diverse native vegetation.
According to Solitude Lake Management, “Not only does a monoculture reduce species richness within a waterbody, but it also decreases available open water habitat for other species utilizing the wetland.” https://www.solitudelakemanagement.com/cattails-good-bad-successfully-managed/
In summary, invasive cattails form dense monocultures that crowd out diverse native plant species and reduce vital habitat resources for wildlife dependent on wetland ecosystems.
Damage Infrastructure
The dense root masses of cattails can cause significant damage to infrastructure in wetland areas, such as drainage systems, pond liners, dikes, and water control structures. The fibrous root systems penetrate deep into the soil, growing horizontally in a dense mat. According to the USDA, cattail roots can extend horizontally up to 2.5 meters from the plant and penetrate over 2 meters deep Cattail Use in the Landscape.
As the roots spread, they can clog drainage pipes, cause leaks in pond liners, and disrupt the integrity of earthen dikes. The tangled mat of roots also collects debris and sediment, exacerbating drainage issues. Cattails will readily colonize drainage ditches, stormwater ponds, and other human-made water systems. Their rapid growth impedes water flow, requiring increased maintenance to clear blocked infrastructure. Removal efforts often damage liners and infrastructure as the dense root masses are pulled out.
Moreover, the accumulation of cattail litter and debris along shorelines and beaches necessitates continual cleanup. As litter decomposes, it releases nutrients that spur further cattail growth. Cattails growing along docks, piers, and swimming areas create nuisance conditions. Their spread diminishes recreational uses and access to waterways.
Degrade Water Quality
Large stands of cattails can degrade water quality in several ways. As cattails die off at the end of each growing season, decaying cattail litter accumulates in the water. This decaying organic matter can reduce dissolved oxygen levels through microbial decomposition. Low oxygen levels are harmful to fish and other aquatic life (https://www.solitudelakemanagement.com/cattails-good-bad-successfully-managed/).
Additionally, dense cattail growth traps sediment that would normally flow through aquatic systems. The trapped sediment increases turbidity, degrades habitat, and elevates nutrient levels that stimulate further cattail growth (https://www.producer.com/crops/cattails-suck-floating-water-filters/). Unchecked cattail expansion can therefore trigger a negative feedback loop of expanding stands and deteriorating water quality.
Impede Navigation
Dense stands of cattails along shorelines can severely impede boat navigation and access to land. As the plants proliferate, they form thick mats that make it difficult for boats, canoes, kayaks, and other watercraft to navigate through the vegetation. The density of the stands prevents clear passage to shorelines, docks, and boat launches. According to the Missouri Department of Conservation, dense cattail stands can entirely choke small streams and lakes, making them almost impenetrable by boats. Their rapid growth allows them to quickly restrict navigation channels and shoreline access points.
Decrease Property Values
Cattail infestations can significantly decrease property values due to reducing the aesthetic appeal and recreational opportunities of a waterbody.
As cattails spread rapidly to form dense stands, they crowd out open water areas and obstruct views. This diminishes the scenic beauty of lakes, ponds, and wetlands that would normally enhance property values.
Thick cattail growth also impedes activities like boating, fishing, and swimming that make waterfront properties attractive to buyers. Reduced access and enjoyment of the water due to prolific cattails growth is a major detriment to property values.
One study found that managing cattails to open up views and access increased shoreline property values by 15-25%. Keeping cattails under control is key to preserving the natural beauty and recreational potential that defines desirability and values of waterfront real estate.
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Are Cattails Good or Bad? How Can They Be Successfully Managed?
Control and Removal
Removing established cattail stands can be very challenging due to their extensive root systems. Cutting or mowing only provides temporary control as the plants quickly re-sprout from the surviving rhizomes. For more permanent removal, the root system needs to be disrupted.
Herbicide application is one of the most effective methods for controlling cattails. Glyphosate formulations like Rodeo and Imox can provide selective control when applied directly to actively growing foliage. It may take multiple yearly applications to fully eradicate established stands. Always follow label directions carefully when using aquatic herbicides.
Other physical control methods include dredging to remove the entire plant and root mass, smothering with plastic or fabric barriers, or repeated cutting and removal of regrowth over several seasons. Freezing conditions in winter can help reduce cattail stands in colder climates. Regardless of method, controlling cattails requires a persistent multi-year effort to stop rhizome re-growth.