Scientific name: Myriophyllum alterniflorum DC.
Common name: Alternate Water-milfoil
Description
Habit: A hairless, submerged, aquatic perennial.
Stems: Weak and trailing, aquatic, to 1.2 m long.
Leaves: Stalkless, without stipules, in whorls of 4; pinnately divided into 5-8 pairs of narrow-linear segments.
Flowers: Small and inconspicuous, mainly unisexual, in clusters forming a loose spike rising above water, with bracteoles; spikes nodding in bud, erect in fruit; lowest bracts resembling the leaves, upper ones entire or toothed; sepals inconspicuous or absent; petals 4, yellow and streaked with red, oval, about 2 mm, falling early, often absent from female flowers; ovary superior.
Fruits: 4 1-seeded nutlets.
Habitat: Lakes, rivers.Distribution: Occasional to frequent.
Native status: Native
Of conservation interest: No