Weeds - Identification of Injurious Weeds (PB4192)

BROAD-LEAVED DOCK
Rumex obtusifolius

Mature plant (Maggy Milner)

Young plant (Maggy Milner)

Rumex obtusifolius

Broad-leaved Dock

A, upper part of stem with a leaf and a lateral branch, and a leaf from the middle part of the stem; B, fruiting-perianth enclosing the fruit and transverse section of same showing seeds; C, plant.

Not to scale.

Young plant:

Seedlings emerge from September through to summer with an opposite pair of narrow diamond-shaped or strap-likecotyledon leaves. The true leaves then emerge one at a time unrolling to form a roughly oval or elongated heart-shaped structure that is green but tinged with purple. Plantlets regenerated from root fragments more closely resemble the adult plant. Broad-leaved docks usually remain vegetative for their first year.

Adult plant:

This dock which has a perennial rootstock produces a basal rosette of large, broad, oval to oblong leaves up to 25cm long with a strong central vein and rounded, backward pointing lobes at the base. Flowering is from late June onwards with the stems typically up to 100cm tall but sometimes reaching 150cm. The flowering stem is loosely branched with numerous clusters of small reddish-brown flowers which have more the appearance of seeds. The flowering stems die back after producing seeds.

Broad-leaved dock is distinguished from curled dock by the broader leaves. The fruit is roughly triangular with one or two swollen seeds. The thin wing or membrane surrounding the seeds has an irregularly toothed edge.

The long tap root of this plant is more prone to be branched than that of curled dock. Both species are widespread and can hybridise so that intermediate plants occur.

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