Notice:  This highly invasive plant has caused millions of dollars worth of damage and control costs in many countries around the world.  In 1995 this weed was found in the US.  In 1999 it was found in Arizona.  Help to prevent the spread of this harmful pest; be alert for its presence in waterways, water garden ponds, and nurseries.

                                 Ovate Floating Leaves                            Hair-like Structures on tops of leaves        Root-like Structures Identification:  Free floating aquatic fern, made up of pairs of oval leaves, green to brown leaves up to 1 ½” long, that are connected by a horizontal stem.  The top of each leaf has many tiny hair-like structures, that split then rejoin at the tips to form an egg beater-like structure.  Beneath the water at each node is a dissected leaf which looks like and  functions as a root.  Infertile, hairy,sporocarps about 1 mm in diameter hang below the roots in long straight chains.

 
Additional information:

v found in the Colorado River in 1999

v affects irrigation, recreation, drinking water supplies

v S. molesta populations can double in size in less than 3 days.

v can produce a mat of growth over the water from up to 2 feet thick.

v it blocks off light to plant growth below

v reduces the exchange of oxygen into the water, further depletes the dissolved oxygen content as old growth decomposes

v impacts migrating birds since covered ponds can no longer be seen

v clogs boat propellers and engine intakes

Likely means of spread:  It will quickly spread with wind or water currents.  It is spread between waterways by bait buckets, and fragments on boats, motors, trailers and in livewells.  Use as a landscape plant has been known to spread the plant great distances.  Has recently been found for sale in nurseries in Arizona!