The History Of The Curly Leaf Pondweed


Curly leaf pondweed originated from Europe, Africa, and Australia. It was accidentally introduced to United States aquatic life in the mid-1880s by hobbyists who used it as an aquarium plant.

In addition to spread by natural causes and recreational activity, this aggressive underwater plant also got to Canada by being planted intentionally for waterfowl and wildlife habitat. Water contamination plays a role for this spreading.



 Treating curly leaf pondweed near the shoreline


                           Economic Impact

In the spring, it forms dense mats which interfere with recreation and limit the growth of native aquatic plants. Unpleasant views and odors are the result of decomposing vegetation that was washed upon shore.
A large amountof curly pondweed can block access to docks and sport fishing areas during the spring and early in the summer months.Cost for control and can range in the Millions per lake. It creates unpleasant stinking messes on beaches. Curly-leaf pondweed forms surface mats that interfere with aquatic recreation, such as boating. Curly Leaf has many economic impacts on Property Values, Tourism, Fishing and Recreational uses of a body of water with curly leaf present.

Property owners have to face low property costs selling lakefront property. Fishermen may also avoid lakes infested
with Curly Leaf Pondweed because of the problems followed by it.Tourists will avoid staying at
resorts and campgrounds in which they have to face the concequences of Curly Leaf Pondweed. Other recreational activities that will suffer are boating and swimming, when these mats of vegetation are present.


 Enviornmental Impact

New plants form under the ice in winter, making curly-leaf pondweed one of the first nuisance aquatic plants to emerge in the spring.

The impacts on the aquatic food web in the lake are severly great. Curly Leaf Pondweed blocks out vital light required for
native species growth. This also impacts the food chain of the waterbody.
With the lack of light, Phytoplankton can not grow. And if that happnes, fish dont have a sustainable food source that lasts. Causing fish to die of starvation by falling prey to predators.




 Curly leaf pondweed Distribution in Canada and U.S [These are the areas that are affected the most].

The Ecozone that is affected the most is the Boreal Sheild.


Many things can be done to prevent and slow the spread of this species. however, once a body of water is contaminated, its almost practiacally impossible stopping the tuff and frequent reproduction of this water plant. The expenses for removal are very high and not long lasting or effective as well.

Some control options may be:


Curly-leaf pondweed can be removed by raking or seining it from the pond but will reestablish from any remaining roots.

Fertilization to produce a phytoplankton or algal "bloom" prevents the establishment of most bottom rooted aquatic weeds and produces a strong food chain to the pond fish.

Non-toxic dyes or colorants prevent or reduce aquatic plant growth by limiting sunlight penetration, similar to fertilization.


Grass carp will pause control aquatic vegetation the first year they are stocked. They will consume curly-leaf pondweed. Grass carp stocking rates to control curly-leaf pondweed are usually in the range of 7 to 15 per surface acre

Chemical Control There are a small number of aquatic herbicides that can be used to control curly-leaf pondweed. Fluridone usually has to be applied to an entire lake and requires 30 days to knock down curly-leaf pondweed.

Habitat manipulation Habitat manipulation such as drawdowns and dredging can also be used to manage curly-leaf pondweed.ure Fall drawdown can kill the plants by exposing them to freezing temperatures. Dredging can be used as a control by increasing the water depth. In deep water, the plants do not receive enough light to survive.

 How Does Curly Leaf Pondweed Spread?

It is known to be spread from one body of water to another. It is rather unintentional in this case for the transfer of turions and seeds, but turions are more common. Another explanation may be the spread of the contaminant in water used to transport fishes and fish eggs to hatcheries. Turions are hardened stem tips on plant fragments. It is carried and spread by untrailered boats, personal water crafts, boat motor propeller, trailer, water intake of a jetski, etc. Curly leaf has now spread to Alberta, British Columbia, Ontario, Quebec and Saskatchewan.  

Removal & Maintainence of curly leaf pondweed. (picture above)


Curly -Leafed Pondweed- Managment Options. 2000 -2008. Aquaplant Texas Agrilife Extension Serevice, Department of wildlife and Fisheries Sciences, Texas A&M university. 14 Dec. 2008  <>.

Curly- leaf Pondweed (Potamogeton Crispus). 2008. Minnesota Department of Natural Resources. 12 Dec. 2008 <>.

Curly- Leaf Pondweed in the Great Lakes Region.17 Sept. 2008. Great Lakes Information Network. 12 Dec. 2008       <>.

Exotic Plants Identification Page. 2002. Professional Lake Managment. 15 Dec. 2008 <>.

Potamogeton Crispus. 6 Dec. 2008. USGS Nonindigenous Aquatic Species Database. 14 Dec. 2008 <>.









Curly- Leaf pondweed infestation Minnesota   ----------->

This is where this species originated from back in 1910.