Wetland Plants of Wisconsin

Alisma plantago-aquatica L.
water plantain
plants on muddy shore one plant leaf flower head of achenes and 3 separate achenes

Water plantain is an early colonist of muddy soils, pond edges and roadside ditches. The inflorescence branches repeatedly to produce numerous small white, 3-petaled flowers. Each flower matures into a head of achenes as shown above. Plants previously referred to as Alisma plantago-aquatica L. are now divided into two species (A. triviale Pursh.and A. subcordatum Raf.), distinguished primarily by size of flowers and achenes as follows:

  petal length (mm) achene length (mm) width of fruiting head (mm)
Alisma triviale 3.5-6.0 2.1-3.0 4.1-7.0
Alisma subcordatum 1.0-3.0 1.5-2.2 2.0-4.0


A. subcordatum

A. triviale

known Wisconsin distribution


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