Dock Weed (Rumex spp)

Once you read this you will be able to:

• Identify Docks.
• Know the habitat of the Dock Weed.
• Know the best cultural and chemical options to control Dock.

In Australia, Docks starts to grow in the Winter, and flower and fruit by early Summer. This is when the above-ground branches die and turn brown.

Spring and Autumn are the main germination periods. Young Dock Weed plants overwinter as a rosette, and above ground growth is slow until a taproot develops.

Category: Broadleaf (Dicot).

Photosynthetic Pathway: C3 Weed.

Flower: Dock flowers are small, green and in clusters at the end of the upright stems. The flower clusters of Broadleaf Dock are not as dense and closely spaced as those of Curly Dock Weed. Once the flowers die, the fruit takes on a rusty-brown color, and can stay on the plant over winter.

Height: Dock Weeds are 50 to 130 cm tall.

Leaf length: The leaf blade is thin, egg-shaped, and around 25 cm long. It has a blunt to pointed tip and its base is round-lobed.

Leaf width: The leaves are about 12 cm wide.

Reproduction of Docks.

Broadleaf and Curly Dock Weeds spread by seed, which falls close to the plant. The seed also spreads due to animals, machinery or humans that brush against them. They also disperse by wind.

The fruit can disperse long distances by water, due to a corky appendage called a callosity that allows them to float.

Seeds of Broadleaf Dock survive at least 40 years under favourable conditions, and Curly Dock seeds can remain viable in the soil for up to 80 years.

About half of the Curly Dock Weeds die after they flower, and a typical plant lives about three years. Both species are relatively short-lived perennials. Less than 2% of Broadleaf Dock and 4 to 24% of Curly Dock survive for more than four years.

The crown and upper taproot also regrow from fragments left behind during soil cultivation.

Comments: Both Curly Dock and Broadleaf Dock Weed are big seed producers. Docks are an aggressive weed, and have a deep root system that depletes the soil of nutrients and moisture. They are frost and drought tolerant.

Habitat: Docks indicate moist to wet ground, which is at least occasionally waterlogged. Swamps and marshes are its common habitats. Curly dock is an indicator of compaction.

For more information on weeds check out our weed ID Chart.

You can control Dock Weed by cultural and chemical means, but successful management of this weed is best if you adopt an integrated approach.

• Both Curly and Broadleaf Dock Weed are difficult to control by hand due to their deep taproot. If the root breaks off while you try and hand remove the plant it regenerates from the part that remains in the soil. A better option is to cut them off about 50 mm below the surface with a shovel.
• Regular mowing before Dock Weed seeds is effective in reducing seed production.
• Anything that increases the ability of desirable turf grass to out compete Docks is a good thing. So deal with any soil compaction, and encourage a dense grass cover.

Avoid scalping or mowing too short as this will limit any gaps in the canopy for Dock Weeds to emerge. Work in Ireland actually shows that docks germinate and grow better when there are high K levels in the soil.

Seeds of Dock Weed need light to germinate, and so a thick, dense cover will help to prevent it establishing. Once this weed gets too big, say around the 5 to 6 leaf stage onwards, turf grass will not outcompete this weed.

Another key to its management is to have a fertilie soil. This means adequate levels of N, P and K, plus the right soil pH for the grass you have.

Non Selective Herbicides for Dock Weed.

You can use Glyphosate as a non selective option to control this weed, although herbicide resistance has been reported overseas. If you use Glyphosate for Dock Weeds and water quality is an issue then we recommend the use of ProForce Manta Ray.

Other options for Dock Weed include:

• Cortex Duo.
• Numchuk Quad.