Persicaria amphibia (Water Smartweed) - photos and description

 

 

 

 

 

 

 

General: Perennial with long, creeping runners above ground. Plants terrestrial or aquatic. Plants have small hairs on stem below the spike, remainder of stem glabrous.

Flowers:  Flowers are small, pink in a dense spike. Spikes measured at 5 cm long.

Leaves: Stem leaves opposite. Leaves oblanceolate, white midrib, leaf measured at 14 cm long and 3.5 cm wide. Leaf top and bottom with very short hairs on nerves.

Height: Stem length listed in Flora of Alberta to 1 m.

Habitat: Sloughs, streams, rivers in the prairies, parklands, and boreal forest.

Abundance: Common.

Origin: Native. 

Synonym: Listed in some of the field guides we use as Polygonum amphibium, and Polygonum coccineum

Budd's Flora
, and, ITIS, combine Polygonum amphibium, with Polygonum coccineum, while Flora of Alberta, and Checklist of the Vascular Plants of Saskatchewan split the two species. I follow ITIS naming, and so am listing this plant as Persicaria amphibia (Polygonum amphibium). If following the Flora of Alberta, this plant is probably P. coccineum, because it has hairs on its peduncle, and spikes > 4 cm in length.

When and where photographed: Photos taken August 6th, shore of the Red Deer River, boreal forest, about 450 km northeast of our home in Regina, SK.