Smartweed (Polygonaceae family):
Curled dock: Rumex crispus L. and Broad-leaved dock: Rumex obtusifolius L.
EPPO code:
RUMCR, RUMOB
Other names:
Curly dock, blunt-leaved dock

Species information

Lifecycle:
Perennial.
Propagation:
Reproduces by seed.
Emergence:
Docks germinate mainly in early spring and autumn with a higher percentage of seed germinating when on the soil’s surface rather than when buried (Pye and Andersson, 2009).
Habitat:
Docks can be found throughout Ontario. They are most often found in moist waste places, along fencerows and roadsides, and in pastures. They are occasionally found in cultivated fields.
Competitiveness:
No data exists on the competitiveness of docks.

Identification clues

Seedling

Cotyledon leaves:
Elongated.
Leaves (curled dock):
The leaves of curled dock are long (10–30 cm) and narrow with very wavy margins. They are green with reddish purple blotches.
Leaves (broad-leaved dock):
Broad-leaved dock leaves are much wider than those of curled dock; the base is heart-shaped. They have wavy margins and the surface is green with reddish-purple blotches.

Mature plant

Stems:
Both species have a membranous sheath, called an ocrea, which wraps around where the leaf stem attaches to the main stem. Leaves are alternate.
Flowers:
Both species have small, green flowers clustered in whorls around the branches of the main inflorescence.
Fruit:
Docks produce brown fruit with three wing-like papery sections that contain one prominent, egg-shaped seed. Broad-leaved dock fruit differs in that the wing-like papery sections have irregularly toothed margins whereas curled dock has entire margins.
Roots:
Strong and deeply penetrating taproot.
The elongated cotyledons and round first leaves
The elongated cotyledons and round first leaves.
The long narrow leaves of curled dock with very wavy margins
The long narrow leaves of curled dock with very wavy margins.
The comparatively wide leaves of broad-leaved dock
The comparatively wide leaves of broad-leaved dock.
The membraneous sheath (called an ocrea) surrounds the stem of both docks at each node
The membraneous sheath (called an ocrea) surrounds the stem of both docks at each node.
Fruit of curled-dock with its three-winged papery sections with entire margins and large seed in the middle. In comparison, broad- leaved dock would have fruit with irregularly toothed margins.
Fruit of curled-dock with its three-winged papery sections with entire margins and large seed in the middle. In comparison, broad- leaved dock would have fruit with irregularly toothed margins.