Rumex crispus (Curly Dock) - photos and description
Fruit in above photo.
Fruit in above photo, valve margins entire or lightly erose.
Fruit in above photo, valve margins entire or lightly erose.
Pedicels jointed.
Viewing down a fruit from the apex viewing all 3 valves, one
tubercle is larger than the other two tubercles.
Flowers in above photo.
General: Stout, erect, mostly single-stemmed perennial. Stem glabrous.
Flowers: Inflorescence tall and narrow. Flowers small, greenish.
Fruit: Fruit is a three-sided achene, each side triangular in shape and known as a valve. The valves are entire to lightly erose (irregularly toothed). the grains (tubercles) are unequal in size, one grain noticeably larger than the other two. The largest grain is 1/2 the length of the valve. We measured a valve at 5 mm long by 4 mm wide, a large tubercle at 2.5 mm long and a small tubercle 1.5 mm long.
Leaves: Leaves alternate, linear-lanceolate, the margins strongly undulate (wavy), we measured a leaf at 200 mm long by 38 mm wide. Leaves reduced in size upwards. Leaf highlighted in photo above was 10 cm long by 2 cm wide. Top of leaves glabrous, bottom of leaves with very short hairs on the main nerve.
Height: Height is listed in Flora of Alberta to 80 cm, we measured plants to 94 cm tall.
Habitat: Moist ground.
Abundance: Common.
Origin: Introduced.
How to identify this species: Pedicels jointed, 3 grains per fruit with 1 grain noticeably larger than the other 2 grains, valves with entire to lightly erose margins, leaves crinkled (Wetland Plants of the Northern Great Plains).
Similar species: This plant might be confused with Rumex stenophyllus which also has wavy-margined leaves, and jointed pedicels. However, that plant has valves with coarse teeth, and has 3 tubercles per fruit roughly equal in size, whereas Rumex crispus has valves with entire to lightly erose margins, and its 3 tubercles are of unequal size - one larger tubercle, two smaller tubercles.
This plant might be confused with Rumex pseudonatronatus which also has wavy-margined leaves, and jointed pedicels. However, that plant has only 1 weakly developed tubercle per fruit, whereas Rumex crispus three tubercles per fruit.
When and where photographed: Photos taken July 15th, moist, muddy shore of small lake, about 70 km southeast of our home in Regina, SK.