Swamp Dock

Rumex brownii Campdera

Family: - Polygonaceae.

Names:

Rumex is derived from the Latin name for Sorrel.

Brownii commemorates Robert Brown(1774-1858) a famous botanist who collected and named many Australian plants.

Swamp Dock because it is prevalent in wet situations. Dock is from the Old English docce meaning a coarse weedy herb.

Other names:

Brown Dock

Slender Dock.

Summary:

An erect plant with a perennial rootstock and annual tops of a rosette of large oblong leaves and almost leafless , sparsely branched stems up to 1 metre tall that turn dark brown with at senescence. The small flowers from September to December produce single seeded fruit with small hooked spines.

Description:

Cotyledons:

Two. The cotyledon has a blade 7-12 mm long with a petiole of about half that length, and is hairless. The seedling has only a short hypocotyl and no epicotyl.

First Leaves:

The leaves develop singly, the first having a blade 10 to 15 mm long with a petiole of about half that length.

Leaves:

Develops a basal rosette. Stem leaves are alternate.

Stipules - Membranous sheath, brown, encircling the stem, 20-75 mm long.

Petiole - Slender, stem clasping, to 170 mm long.

Blade - Oblong to egg shaped, sometimes with a notched base or lobed at the base, 30-170 mm long by 10-40 mm wide, dark green, slightly succulent. Blunt tip. Edges wavy(crisped) and often finely toothed. As the leaves elongate and the base angle becomes approximately 90 degrees.

Stem leaves - Alternate. Not many, on the lower third of the stem, 50 to 80 mm long, petiolate, becoming progressively shorter and more pointed towards the top of the stem. Hairless.

Stems:

Few, erect to curving, slender, fluted, reddish green, 300-1000 mm tall, almost leafless, often unbranched except towards the top. Hairless.

Flower head:

Almost leafless, loose panicle with a few, almost erect, narrow branches.

The flowers are produced on jointed stalks(pedicels) in whorls of 5-16 flowers towards the top of the branches forming long racemes. Racemes are leafless except at the base. Flower clusters tend to be rather smaller, more compact, and more widely spaced than in other Docks.

Flowers:

Greenish red, small on curved, stalks, 1 mm long.

Bracts - Ochreola, translucent, 3 mm long.

Ovary - 3 styles with large, tufted stigmas.

Perianth - 6 segments, 3 inner ones, network patterned, enlarged and close over the fruit.

Stamens - 6.

Anthers -

Fruit:

3 sided achene, initially greenish brown and becoming dark brown with age. Nut enclosed by 3 inner perianth segments or valves, 2.5-4 mm long by 2 mm wide, triangular, with a long hooked tip and 2-5 long hooked or awl shaped teeth on either side. Valves have an obvious network pattern, thickened midrib but no warts(tubercles). Valves not attached to nut. Achene on a curved stalk, 3-5 mm long that holds it away from the stem.

Seeds:

Triangular pyramid, brown nut, 2 mm long by 1.25 mm wide, wider below the middle.

Roots:

Short underground stem on top of a carrot like, thick, contorted rootstock.

Key Characters:

Perennials.

Leaves not hastate, base tapering or truncate, not lobed.

Fruiting perianth inconspicuous.

Perianth lobes 6, the inner 3 larger than the outer.

Flowers bisexual, rarely polygamous.

Flower clusters of 5-8 flowers, distant, without floral leaves except to the lowest ones.

Fruiting valves naked with long, hooked apical teeth and 3-5 teeth on the margins. Apex of valve long, narrow and recurved.

From J.M. Black, N.T. Burbidge.

Biology:

Life cycle:

Annual top, perennial rootstock. Seeds germinate at any time of the year with a peak in autumn and spring. Seedlings develop into a rosette of leaves and form a rootstock. They may or may not flower in their first year. The rootstock forms new shoots in autumn or winter (or spring in western NSW) and quickly produce a basal rosette of leaves. A flowering stem emerges in spring. Top growth dies in summer leaving the perennial rootstock.

Physiology:

Reproduction:

By seed and perennial rootstock.

Flowering times:

Spring in western NSW.

September to December in SA.

December in Perth.

October to December and April in WA.

Seed Biology and Germination:

Exposure to light, alternating temperatures, stratification(chilling of moist seed) and nitrate increases germination.

Some seed is dormant.

Some seed may last for many years in the soil.

Vegetative Propagules:

Perennial rootstock.

Hybrids:

Allelopathy:

Population Dynamics and Dispersal:

The hooked spine seed is spread by attachment to animals or any fibrous material. It is also spread as a contaminant of grain and hay. Cultivation or earth moving machinery spreads the rootstocks and root fragments.

Origin and History:

Possibly native to eastern Australia.

Introduced to WA. First recorded in 1902, now widespread in the lower south west of WA.

Distribution:

ACT, NSW, NT, QLD, SA, TAS, VIC, WA.

Found in most parts of Tasmania. It is more prevalent in the South than in the North, and somewhat localised in distribution.


Courtesy Australia's Virtual Herbarium

Habitats:

Damp low lying areas.

Climate:

Temperate. Mediterranean. Moist warm temperate to subtropical areas.

Soil:

On many soils.

More abundant on winter waterlogged soils.

Plant Associations:

In many communities.

Significance:

Beneficial:

Native plant of eastern Australia.

Detrimental:

Weed pastures, crops, vegetables, orchards, vineyards, roadsides, drains, streams, lawns and disturbed areas

It is only of occasional importance in pasture or crops.

Toxicity:

Occasionally contains potentially toxic amounts of nitrates but nitrate toxicity has not been reported as a field problem. Other docks may occasionally cause oxalate poisoning but it has not been recorded for this species.

Legislation:

Noxious weed of WA.

Management and Control:

Seedlings less than 6 weeks old can usually be controlled by cultivation. Repeated cultivation over summer are required to control rootstocks.

Mowing and slashing are ineffective.

Some selective control in legume based pastures can be achieved by using glyphosate in a blanket wiper in late spring.

Thresholds:

Eradication strategies:

Remove isolated plants by cutting their roots at least 200 mm below ground level.

Apply 800 mL/ha glyphosate(450g/L) plus 40 g/ha Logran plus 5 g/ha Ally plus 1 L of Pulse Penetrant per 400 L of spray mix, 2-3 weeks after the break. Cultivate 5 days later and plant wheat.

OR Apply 1000 mL/ha glyphosate(450g/L) plus 500 mL/ha Dicamba(200g/L) plus 1 L of Pulse Penetrant per 400 L of spray mix, 2-3 weeks after the break and cultivate 5 days later and plant oats or barley.

6-8 weeks after planting apply 5 g/ha of Ally in wheat and barley crops or 750 mL/ha of dicamba amine in oat crops.

In following break crops use triazine or urea herbicides to reduce the establishment of Dock for dormant seed.

In following clover pastures, Spray Graze with 750 mL/ha of 2,4-D amine(500g/L) 6-8 weeks after the break of the season to prevent seedlings establishing. Repeat this annually for at least 5 years.

In bushland, individual plants may be wiped with a mixture of 1 L glyphosate(450g/L) in 2 L water. Small infestations may be sprayed with 0.5g chlorsulfuron(600g/kg) plus 100 mL Tordon 75-D in 10 L of water in winter. This mix controls existing plants and has residual activity to control seedlings about a year. Some seed will remain viable in the soil for 20 years. Plant tall growing perennial species to increase the levels of shade and help reduce re invasion.

Blanket wiping with 1 L glyphosate(450g/L) plus 20 g chlorsulfuron(750g/kg) plus 2 L water in spring is reasonably selective in pastures. This mix may be applied manually to individual plants. On small infestations 0.5 g chlorsulfuron(750g/kg) plus 100 mL Tordon®75-D in 10 L of water in winter will control existing plants and seedlings for about a year. Some seed remains viable for 20 years. 2 L/ha glyphosate(450g/L) can be used selectively in some seasons when dock is green in autumn or summer and the annuals are not. Metsulfuron is also effective. Grazing, mowing and cultivation usually lead to greater stands. Plant tall growing perennial species to increase the levels of shade and help reduce re-invasion.

Herbicide resistance:

Biological Control:

Bio control is under investigation but may not be approved because of the native plant status of this species.

Related plants:

Bladder Dock (Rumex vesicarius)

Broadleaf Dock (Rumex obtusifolius)

Clustered Dock (Rumex conglomeratus)

Curled Dock (Rumex crispus) is a tall plant up to 1.5 m high with pointed oval leaves that are 4-24 cm long. The leafless inflorescence has densely clustered flowers and fruits. The fruit valves are reddish brown, swollen in the centre, with smooth margins and lacking teeth.

Fiddle Dock (Rumex pulcher) is a plant to 50 cm tall with rounded oblong leaves, the basal ones sometimes slightly constricted in the middle and appearing fiddle-shaped. The leaves are 4-15 cm long. The leafy inflorescence has distant whorls of flowers and fruits. The fruit valves are brown, swollen and warty in the centre and the margin has prominent stiff teeth.

Mud Dock (Rumex bidens)

Rambling Dock (Rumex sagittatus)

Shiny Dock (Rumex crystallinus)

Sorrel (Rumex acetosella)

Wiry Dock (Rumex dumosus)

Plants of similar appearance:

Spiny Emex (Emex australis) looks similar especially when young.

References:

Auld, B.A. and Medd R.W. (1992). Weeds. An illustrated botanical guide to the weeds of Australia. (Inkata Press, Melbourne). P207. Diagram. Photo.

Black, J.M. (1965). Flora of South Australia. (Government Printer, Adelaide, South Australia). P281. Diagram of seed.

Burbidge, N.T. and Gray, M. (1970). Flora of the Australian Capital Territory. (Australian National University Press, Canberra). P153, 155. Diagram.

Cunningham, G.M., Mulham, W.E., Milthorpe, P.L. and Leigh, J.H. (1992). Plants of Western New South Wales. (Inkata Press, Melbourne). P234.

Everist, S.L. (1974). Poisonous Plants of Australia. (Angus and Robertson, Sydney). P583.

Gilbey, D. (1989). Identification of weeds in cereal and legume crops. Bulletin 4107. (Western Australian Department of Agriculture , Perth). P24-25. Diagram of seed.

Hussey, B.M.J., Keighery, G.J., Cousens, R.D., Dodd, J. and Lloyd, S.G. (1997). Western Weeds. A guide to the weeds of Western Australia. (Plant Protection Society of Western Australia, Perth, Western Australia). P200.

Hyde-Wyatt, B.H. and Morris, D.I. (1975). Tasmanian weed handbook. (Tasmanian Department of Agriculture, Hobart, Tasmania). P58-59. Diagrams.

Lamp, C. and Collet, F. (1990). A Field Guide to Weeds in Australia. (Inkata Press, Melbourne).

Lazarides, M. and Hince, B. (1993). CSIRO handbook of economic plants of Australia. (CSIRO, Melbourne). #1072.3.

Marchant, N.G., Wheeler, J.R., Rye, B.L., Bennett, E.M., Lander, N.S. and Macfarlane, T.D. (1987). Flora of the Perth Region. (Western Australian Herbarium, Department of Agriculture, Western Australia). P115.

Parsons, W.T. and Cuthbertson, E.G. (1992). Noxious weeds of Australia. (Inkata Press, Melbourne). P545-547. Photos.

Acknowledgments:

Collated by HerbiGuide. Phone 08 98444064 or www.herbiguide.com.au for more information.