Rumex obtusifolius

Scientific Name	Rumex obtusifolius L.
Common Names	English: Bitter dock, broad-leaved dock; German: Stumpfblättriger Ampfer, French: Patience sauvage; Spanish: Acedera, romaza
Description	Perennial, seed-propagated and root-propagated weed with vigorous, yellowing root stock, spreading through sprouts. R. obtusifolius has a deep taproot and is very similar to Rumex crispus.

Characteristic Features

Big cordate leaves with crisped margins. Often, the veins of the lower leaves are red.

Cotyledons

Lanceolate, ca. 20-25 mm (0.78 - 0.98 inch) long, with marked petiole.

Stems

Erect, usually several branches, sometimes red-splotched, up to 120 cm (47.2 inch) high.

Leaves

Lower leaves large, broad, ovate, cordate at the base, slightly ruffled, blunted, upper leaves smaller and more slender, oblong-lanceolate.

Flowers

Green, inconspicuous, in many-blossomed inflorescences that turn rust red.
Inner involucral leaves dentate on the margins.

Flowering Period

Summer.

Fruit

Triangular achene, often turns bright red, about 2 mm (0.078 inch) long.

Seeds

Germination in spring.
The hard-coated seeds are ovoid-oblongoid, rather large in size.

Viability of Seeds

Several decades.

Propagation

By seed and vegetatively.
Ca. 7,000 seeds/plant.

Habitat

Fields, gardens, waste ground, disturbed sites, damp woods, gravel bars, roadsides, railroads.

Soil

Loamy fertile soil.

Additional Crop Information

Meadows, pastures, partly in arable fields after reduced tillage practices.

Agricultural Importance

R. obtusifolius is a most important perennial weed, which is common in meadows and pastures. Low preference or even rejection by feeding animals may result in increasing dominance on grazed land.

Useful non-chemical contribution to Integrated Weed Management

Hoeing or digging can be effective if the whole plant, including the root, can be removed. Old docks, especially those with well developed tap roots will often survive cultivation.

Chemical Control

Targeted application of (often) non-selective herbicides (spot spraying).