Eurasian water milfoil

Family: Haloragaceae
Scientific name: Myriophyllum spicatum
Description: Plant Form: Mostly submerged aquatic perennial herb. Size: Rooted up to 7 m deep. Stem: Hairless, reddish-brown to whitish-pink, thin, branching near the water surface. Leafless towards base. Leaves: Feather-like, divided into many pairs of leaflets, olive-green, 1.5-4 m long, in a whorl around the stem, usually submerged. Flowers: In whorls of 4 above water in upright spike 5-20 cm long. Male flowers above female flowers and have pink petals, whereas female flowers lack petals. Fruit and Seeds: Egg-shaped, red, 3 mm long, containing 4 dry 1-seeded nutlets. Habitat: Ponds, reservoirs, lakes. Distinguishing Features: Parrot's feather (Myriophyllum aquaticum) leaves are similar, but don't tend to be submerged. Native Watermilfoil (Myriophyllum salsugineum) also tends to have emergent leaves.

Example images for this weed