What is dock?
There are nine species of dock in Tasmania, including several native species. Three docks are significant pasture weeds in Tasmania: curled dock (Rumex crispus), broad-leaved dock (Rumex obtusifolius), and fiddle dock (Rumex pulcher).
How to identify dock
- Dock species are very similar in appearance, and identification in the vegetative (non-flowering) stages is difficult.
- The common curled dock grows to one metre in height. The leaves are broadly spear-shaped, pointed at the tip with a wavy leaf margin. The stem is solid with longitudinal grooves. Several stems can be grown from a single base, with branching occurring towards the top.
- Green flowers form in clusters and the seeds are found in a three-winged reddish-brown fruiting body. A reliable identification of the dock species depends on examination of the fruit.
- Docks are perennials, or long-lived plants, and develop a deep tap root. Docks usually germinate in autumn and develop into rosettes (a whorl of leaves at ground level) through the winter. A flowering stem emerges in spring and the seed matures through summer. The stems usually die back during autumn and the plants over-winter as rosettes.
- For help in identifying docks, search the
Dennis Morris Weeds and Endemic Flora Database. If you are still in doubt about the weed you are dealing with, contact Biosecurity Tasmania on 03 6165 3777 for help.
Image top: curled dock young plant, (© Louis M. Landry).Image top row left: curled dock, (© Saint Mary's College of California).Image top line row right: curled dock in pasture, (© Louis M. Landry).
Image bottom row left: curled dock, (© Saint Mary's College of California).Image
bottom row
right: curled dock seed closeup, (© S Matson).
Dock in Tasmania
- Docks are not declared weeds in Tasmania.
- Curled dock and broad-leaved dock are common in the higher rainfall areas of Tasmania, while fiddle dock is more tolerant of dry conditions.
- Curled dock and broad-leaved dock thrive in irrigated areas such as dairy properties (especially in areas watered by dairy washings), orchards, and plantation crops such as hops. Curled dock and broad-leaved dock can be strongly competitive in pasture, and compete with establishing crop plants such as lucerne.
- Fiddle dock can become a serious competitive weed in pastures, and can also cause problems in lawns and recreational turf.
See also
Herbicides for Docks Control
Weed Links and Resources
Other useful links
Pest Genie
APVMA
Dock Control Guide
Do
- Plan your control program, this will save time and money in the long-run;
- Consider the impact of your control methods on off-target species, especially if herbicides are used;
- Ensure machinery and equipment is washed down between sites or prior to contractors leaving site;
- Get in early - for new infestations, eradicate before the plants reach the flowering stage: once plants begin seeding, control becomes more difficult and expensive; and
- Carefully time your use of herbicide for best results (see
Herbicides for docks control for more information);
- Coordinate your control program with neighbouring landholders where your weed problem crosses property boundaries;
- Revisit and regularly inspect the site and ensure follow-up is undertaken;
- Use a combination of different control methods; and
- Establish vigorous pasture (or native species) after removal to reduce re-infestation.
Don't
- Don't introduce dock to dock-free areas (e.g. by failing to wash down machinery and equipment between sites);
- Don't start your control program without first planning your approach;
- Don't allow dock to flower and set seed before treatment;
- Don't rely on one attempt at removal - follow-up is essential; and
- Don't rely on just one control method.
Spread of dock
- Docks spread mainly by seed. Most dock seed falls close to the parent. Soil movement may also distribute seeds.
- Damage to the root system can create root fragments which can be spread by cultivation, allowing new plants to form from each fragment.
- See the
Washdown Guidelines for Weed and Disease Control for detailed information on how to wash-down equipment and personnel to reduce the chance of spreading docks.
Physical removal and cultivation
- Hoeing or digging can be used to remove docks, provided the entire tap root is removed.
- Seedlings and young rosette docks can be killed by cultivation. However, old docks with well developed tap roots will often survive cultivation, especially in autumn or winter.
- Docks regenerate readily from root fragments and will often survive a single cultivation. Repeated cultivations may be necessary to eradicate docks.
Grazing
- Vigorous well managed pasture helps prevent dock establishment.
- Avoid over and under-grazing. Block grazing is strongly recommended.
- In dairy pastures, winter grazing should be controlled to prevent pugging of the soil.
- Attention to drainage of pasture areas which get waterlogged or lie wet for extended periods will reduce the potential for dock invasion.
Biological control
- Biological control is the use of a living species, usually an insect, mite or disease, to control a weed;
- Biological control will not eradicate docks, but can be used in conjunction with other control methods;
- Biological control agents that have been released in Tasmania include the clear wing dock moth.
- For more information on biological control programs in Tasmania contact the
Tasmanian Institute of Agriculture
Chemical control
- A number of herbicides are registered for use on docks in Tasmania. See Herbicides for Dock Control for more information.
- In newly-sown pasture, seedling docks are best controlled with MCPA sodium at 250g a.c./ha (1.0 L/ha of a 250 g/L formulation). MCPA will damage clover and must not be applied until young clover plants have 2-3 trifoliate leaves, and the grass seedlings are 100 mm.
- MCPA or 2,4-D amine can be used to control small and medium sized docks in established pastures. More effective control can be obtained by adding dicamba to the MCPA or 2,4-D solution where clover damage is not a concern.
- For control of large docks, asulam, 2,4-D ester, or metsulfuron-methyl are required. Repeat treatments may be necessary. All of these herbicides may severely damage or eliminate clover from the pasture; for up to 12 months in the case of metsulfuron-methyl. Metsulfuron-methyl may also damage ryegrass. Application of a nitrogen based fertiliser may be required to maintain pasture productivity in such situations.
- In turf, dicamba plus 2,4-D plus mecoprop, or dicamba plus MCPA or dicamba plus mecoprop should be used. Treatment should be carried out in early spring (September or early October) when the grass has started to flourish, and may be repeated about 8-12 weeks later. Treatment in autumn, about six weeks after the autumn break should eliminate autumn germinating seedlings. Label recommendations for application rates should be followed.
Herbicides for Dock Control