Hydrilla: World's most invasive aquatic plant found in Michigan for the first time

Hydrilla, an invasive aquatic plant which can multiply itself in various ways, has now been found in Michigan, US, for the first time. The plant was found by the Department of Environment, Great Lakes and Energy in two small populations in private ponds on residential properties in Berrien Springs in Southwest Michigan.

It was discovered in small patches during routine monitoring for another invasive plant called Parrot Feather, which was found in the pond in 2020.

Both species, Hydrilla and Parrot Feather, are prohibited in Michigan, meaning it is unlawful to sell, posses or import them into the state. Also, both are on Michigan’s invasive species watch list due to their potential environmental threat.

What are invasive species and how?

In terms of biology, invasive species are an introduced species to an environment that become overpopulated and harm its new environment. They are also sometimes called alien species. These species adversely affect habitats and bioregions, causing ecological and environmental damage.

Hydrilla is also an invasive species that has several ways of reproducing, allowing it to spread rapidly, and often outperforming native plants. They can quickly damage single-species infestations and even their small fragments develop into new plants. Hence, it becomes very easy for hydrilla to disperse through water or attach to ornamental plants sold for water gardens.

“It’s not clear how either plant made its way to this pond, but seeds or fragments of the invasive plants may have been attached to ornamental plants installed in past years,” said Bill Keiper, EGLE aquatic biologist.

A team of scientists will now try to determine the origin of hydrilla.

Why should you be concerned?

Hydrilla can grow in both low and high-quality waters and has been found in lakes, rivers, reservoirs, wetlands, ponds and streams. Plants are generally rooted in sediment in water depths up to 25 feet and remain submerged with long leaved-steams floating near the surface. Because it outcompetes native plants, it can quickly fill a lake or pond, choking off recreational access.

Though hydrilla can be treated with herbicide, it is difficult to eradicate because tubers and turions can persist in the sediment for years, and plants can reproduce from even small fragments.

How to identify a hydrilla?

Look for long, slender stems floating near the water surface. Check for these characteristics:

- Pointed, bright green leaves about 5/8 inch long with small teeth on the edges.

- Leaves growing around the stem, generally in whorls of five, but they can range from four to eight.

- Tiny, floating white flowers visible in late summer to fall.

- Small, white to yellowish, potato-like tubers attached to the roots.

(With inputs from agencies)

WATCH WION LIVE HERE