Northern Water milfoil Myriophyllum sibiricum

Plant Family: milfoiln Myricaceae

Northern Water milfoil (Myriophyllum sibiricum) is a submergent plant native to much of North America. It is easily mistaken and can hybridize with Eurasian Water-Milfoil (Myriophyllum spicatum), a highly invasive aquatic species. The easiest way to tell the difference between the two species is to count the leaflets on one side of a leaf. Leaflets (or leaf segments) are the little leaves that come off of what looks like a leaf stem. Northern watermilfoil has 5-10 on each side of the midrib, where Eurasian watermilfoil has 12-20. Be sure not to count them at the very top of the plant since those leaves may still be growing. Both species of plant can be very fast growing and become an issue for lake users.

Timelapse video of Milfoil growing in an aquarium.