Northern Water-plantain

Northern Water-plantain
Northern Water-plantain. Alisma triviale.
Alismataceae, the water-plaintain family.

Plant: Emergent, semi-aquatic plant, growing in or immediately adjacent to water, with basal, long-stemmed, ovate leaves, and a sparse, pyramidal, whorled panicle of small, white flowers, to 3' tall. Perennial.
Flowers: Small, white, 1/4"-3/8", with three white petals and three green sepals, growing in a sparsely-filled cluster with a whorled branching structure (a whorled panicle).
Leaves: Basal, ovate, with long petiole and a rounded to heart-shaped base. Blade up to 10" long.
Fruit: A flattened, button-like disk of scale-like achenes.
Blooming: June-October
Habitat: Wetlands, in and adjacent to shallow water.

Comments: There are two similar species in this genus in our area; the other, Southern Water-plantain, (A. subcordata) is distinguished by its considerably smaller flowers (1/8"-1/4") and a number of technical characteristics (e.g. stamens about as long as the ovary instead of nearly twice as long). The bulb-like bases of the plant are supposedly edible if dried to remove the acrid properites. Sounds a bit iffy.

Where to find it: Scattered widely on the shoreline of the pond, individual plants blooming at different times.