Search Sponsored by:
Wednesday, August 24, 2016
Speculator, NY ,

Bladderwort is an aquatic plant that is sometimes mistaken for Eurasian watermilfoil. (Photo submitted)

Some identification characteristics of Eurasian watermilfoil include blunt leaf tips and large internodal spacing between whorls. (Photo submitted)

Eurasian watermilfoil can hitchhike to new lakes on boat motors. (Photo submitted)

Variable leaf milfoil is bushy. (Photo submitted)


Be on the lookout for four invasive milfoils

Monday, February 24, 2014 - Updated: 8:59 AM

LAKE PLEASANT -- Many concerned recreationists and shoreline owners contacted the Hamilton County Soil and Water Conservation District last summer to report possible sightings of aquatic invasive plants.

Invaders like Eurasian watermilfoil and variable leaf milfoil can degrade aquatic ecosystems, make a day of fishing or boating unenjoyable, and are expensive to manage. Native look-alike plants are sometimes mistaken for invasives, but a few key characteristics can help with identification.

"People are well educated about invasive plants and know when something is not quite right in their favorite lake," explained SWCD Conservation Educator Caitlin Stewart. "They report suspect invaders to us for identification.

"Early detection of invasive species results in rapid response. The sooner an infestation is confirmed, the less expensive it is to manage and the greater the success rate for eradication."

Eurasian watermilfoil is native to Asia and Europe, and was introduced to New York state possibly in the 1940s through ship ballast water or via an aquarium release. Another invasive milfoil, variable-leaf milfoil, is native to some parts of the United States.

Due to its aggressive nature in some Adirondack lakes and other water bodies throughout NYS, the Adirondack Park Invasive Plant Program upgraded the plant from a watch species to an invader.

In Hamilton County, Eurasian watermilfoil has been confirmed in Sixth and Seventh lakes and Lake Algonquin. Variable leaf milfoil has been confirmed in Eldon Lake; Fourth, Fifth, Sixth and Seventh lakes; Lake Durant; Long Lake, Raquette Lake; and Rock Pond.

Without the ecological checks and balances found on their home turf, and because they tolerate a wide variety of environmental conditions, these invasive milfoils can form dense populations.

Fragmentation is the main means of reproduction. They hitchhike to new bodies of water on trailers, boats, motors, kayaks, canoes, deck rigging, pets, gear, seaplanes, wildlife...


A number of adverse impacts may result from aquatic invasive plant infestations. Native plants may be out-competed for growing space, light, and nutrients, resulting in decreased biodiversity.

Other adverse impacts include a loss of valuable habitat for fish, waterfowl, and invertebrates; congested waterways that make fishing, swimming, paddling and boating unenjoyable; devalued shoreline property; and hosting suburb breeding grounds for mosquitoes.

Infestations can be expensive to manage. According to the Great Lakes Aquatic Nonindigenous Species Information System, New York state spends an estimated $500,000 to control Eurasian watermilfoil each year.


"Milfoil species can be difficult to tell apart from one another, causing even expert botanists to cogitate over identification," Stewart says. "Invasive milfoils are sometimes confused with native look-alike aquatic plants like bladderwort or other native milfoils, but can be distinguished with a few key characteristics."

Eurasian watermilfoil has blunt-tipped leaves with (usually) more than 11 leaflets. Leaves are whorled around the stem. A reduced, emergent bract appears above the water, but this can be difficult to spot. Bright red growing tips are another characteristic. If held upside down, the plant droops around the stem.

Variable leaf milfoil has a bottle-brush, bushy appearance. Leaves are whorled around maroon stems that are thicker than Eurasian watermilfoil stems. Leaves are composed of greater than 11 leaflets, and little internodal spacing occurs between whorls. Surface spikes emerge above the water's surface.


Recreationists and shoreline owners can take a few simple steps to help stop the spread of aquatic invasive species. They should check their boat, trailer, and gear for aquatic hitchhikers before leaving the water access.

Plants, animals, and mud should be removed and thrown out in a garbage can or on dry land. Bilge water, live wells, bait buckets, motor, and ballast tanks should be drained before leaving the water access.

Boats, trailers, and gear should be dried for five days (if possible) before re-launching into another water body.

And "Keep those invasive species sightings rolling in," encourage SWCD Manager Elizabeth Mangel.

If you spot a possible invasive plant, deliver a sample wrapped in a damp paper towel to the SWCD office at 103 County View Drive, Lake Pleasant. If possible, keep the sample cool until delivery. Photos are also helpful.

The Hamilton County Soil and Water Conservation District has been working to manage and promote the wise use of natural resources in Hamilton County since 1965. For more information call (518) 548-3991 or visit


Comments made about this article - 0 Total

Comment on this article


Most Popular

  • Viewed
  • Commented
  • Emailed
  1. Hawk plans to remove system, severs ties with town board(1392)
  2. Lasting love: Couple celebrates 70 years of marriage in Northville(686)
  3. Cash, valuables reported stolen from vehicles in Speculator(548)
  4. Broadband speeds to improve by 2018(447)
  5. Beware of phishing, scams when online(428)
  6. A budding philanthropist(395)
  7. Police charge woman with falsely reporting that she was abducted(387)
  8. Strengthen Your Faith - 07/287/20126(383)
  9. Inlet considers whether to keep school open(377)
  10. Wells seniors have a busy summer(364)

Copyright © McClary Media, Inc.

Privacy Policies: Hamilton County Express

Contact Us