Crispus is Latin for curly and refers to the curled or crisped leaf margins.
Curled Dock refers to the curled or wavy edges of the leaves and it membership of the Dock genus. Dock is from the Old English docce meaning a coarse weedy herb.
Summary:
Curled Dock is an erect, several stemmed plant up to 1.5 m tall with long, pointed, oval, crisped edged leaves, 40-240 mm long in a basal rosette and smaller leaves up the stem. It has a red brown, dense, papery seed head formed by erect parallel, leafless branches near the top. Each flower has small floral segments, 6 stamens and 3 styles. The fruit is enclosed between 3 valves (the enlarged inner floral segments).
It flowers from September to January and has fruit with papery wings and 3 elongated warts or tubercles. It has a carrot like perennial rootstock with annual shoots.
Native to Europe and south-west Asia, it has become a weed of creek lines, pasture and disturbed woodland.
Description:
Cotyledons:
Two. Oval, tip round, 12-20 mm long with a petiole 3-5 mm long. Hairless. The seedling has a short hypocotyl and no epicotyl.
First Leaves:
Arise singly, oval to round, 15-20 mm long, with wavy edges and a petiole 10 mm long or longer. Hairless. Later leaves are more elongated and wavy edged.
Leaves:
Forms a basal rosette with alternate stem leaves.
Stipules - Membranous sheath, encircling the stem at the base of the petiole, reddish brown, up to 60 mm long
Petiole - Shorter than the blade, 40-120 mm long, slender.
Blade - Green to bluish green, lance to oval shaped, 95-400 mm long by 25-120 mm wide. Hairless. Leaf edges are wavy or crisped. Tip pointed. Sides convex. Base tapers into the petiole.
Stem leaves - Alternate, narrower and smaller than rosette leaves. Lower ones 150-200 mm with a petiole that is shorter than the blade, upper ones 50-80 mm with a shorter petiole. Hairless.
Stems:
Erect, solid pithy core, stout, smooth, grooved or fluted and 500-1500 mm tall but some may be much taller. May have dark stripes or a red tinge. Hairless or a few hairs. Usually several erect stems from the basal rootstock and short erect branches towards the top that are erect and parallel to the main stems. Acute branching angle.
Flower head:
In ring like clusters of many flowers that are close together in a raceme that is leafy near the base and forming a long, dense, compact, erect panicle. It rarely has spreading branches. Rarely there is a leaf underneath the rings in the lower part of the panicle
Flowers:
Green to reddish. On jointed short, 5-10 mm long, stalks in dense whorled clusters on branches 50-200 mm long emerging from upper leaf axils. Male and female flowers 3 mm in diameter with 3 green petal like sepals on the same plant.
Bracts - Ochreola, translucent, 10 mm long.
Ovary - 3 styles with large, tufted stigmas.
Perianth - 6 segments, 3 inner ones enlarged and close over the fruit.
Stamens - 6,
Anthers -
Fruit:
Achene composed of a nut enclosed by 3 inner perianth segments or valves. Valves 3-6 mm long by 3-6 mm wide, heart shaped to circular, membranous, smooth edged, notched at the base, network patterned. Valves are not attached to the nut. One of the valves sometimes has an egg shaped wart(tubercle) that is much larger than on the other two and rarely there is only one tubercle. The achene is on a slender, curved stalk, 3-5 mm long that holds it away from the stem. Initially green brown and becoming dark reddish brown as the fruit matures.
Seeds:
Triangular pyramid nut, glossy dark brown, 2-3.5 mm long by 1 mm wide, broadest below the middle.
Roots:
Thick underground stem or crown 30-50 mm long merging into a light brown carrot like taproot that is unbranched or sparsely branched. Rootstock up to 300 mm long and 30 mm wide with feeder rots extending to 3000 mm deep and slender laterals extending about 500 mm sideways.
Key Characters:
Perennial.
Leaf base attenuate, not lobed.
Fruiting perianth inconspicuous.
Flowers bisexual, rarely polygamous.
Fruiting valves entire, tuberculate, sub orbicular, 4-6 x 4-6 mm.
Fruits on pedicels as long as the inner lobes (3 mm long).
Panicle dense.
J.M. Black, N.T. Burbidge and G. Perry.
Biology:
Life cycle:
Perennial up to 2m tall. Seed germinates from autumn to spring and it grow into a rosette of leaves over winter and forms a solid taproot. Rootstocks shoot in early autumn and rapidly produce a rosette of many leaves that shade and crowd neighbouring plants. Flowering stems emerge in spring and top growth usually dies off over summer though some rosette leaves may survive in summer moist areas. Most seedling don't flower in their first season under field conditions. Flowers at the middle of the seed head open first then progressively towards the top and then towards the base. Seed ripens 16-20 days after flowering. The old flowering stems remain attached to the plant for most of the following season, though most of the seed has shed by late autumn.
Physiology:
Short days delay but don't stop flowering.
Reproduction:
By seed and perennial rootstock.
Flowering times:
Late spring to summer in western NSW.
November to January in SA.
September in Perth.
Seed Biology and Germination:
Exposure to light, alternating temperatures, stratification(chilling of moist seed) and nitrate increases germination.
Most seed will germinate soon after ripening but develops dormancy with age or burial. Seed left on the soil surface loses some of its viability within 3-5 months.
Optimum temperatures for seed germination depends on the temperatures at which the parents were grown and vary from 100C to 300C
Some seed has lasted in the soil for over 80 years.
Vegetative Propagules:
Perennial rootstock.
Hybrids:
Forms hybrids with Broadleaf Dock (Rumex obtusifolius) and with Swamp Dock (Rumex brownii) to form Rumex X johannes moorei.
Allelopathy:
Population Dynamics and Dispersal:
Papery wings on the seed assist dispersal by wind and pithy warts assist flotation for dispersal by water.
Seed consumed by animals is passed in a viable condition.
Rootstocks readily re shoot after being broken by and/or moved by cultivation.
It is also spread as a contaminant of grain and hay.
Autumn germinating seedling usually have a higher survival rate than spring germinating seedlings. Seedlings may produce rootstocks capable of withstanding summer drought in 30-50 days. Seedlings are very sensitive to competition and usually only survive in relatively bare areas. However, once established they are very competitive. They often rapidly colonise areas that have been denuded.
Each plant may produce 60,000 seeds.
Origin and History:
Europe. North Africa. Asia.
Distribution:
ACT, NSW, NT, QLD, SA, TAS, VIC, WA.
Found in all parts of Tasmania.
Courtesy Australia's Virtual Herbarium
Habitats:
Depressions, damp areas and wetlands.
Climate:
Temperate. Mediterranean. Cool to mildly warm temperate. Sub tropical areas.
Soil:
Wide range from duplex sands to loams and clays.
Rarely found on acid peat or very acid soils.
Plant Associations:
Significance:
Beneficial:
Cattle readily eat young flowering stems.
Has been used as pig food.
Used in herbal medicine for diarrhoea, a gargle, a diuretic and for rubbing on skin to neutralise stinging nettle and other skin irritations.
Used as a tea substitute and a yellow dye.
Does not host Root Lesion Nematode (Pratylenchus thornei) (63).
The large, rapidly growing rosette shades companion species.
Common weed of pasture establishment.
Relatively unpalatable but grazed when other feed is limited.
It is a poor host for Root Lesion Nematode (Pratylenchus neglectus) allowing some build up of numbers (63).
Host for light brown apple moth 654.
Toxicity:
May cause oxalate poisoning in stock.
May cause dermatitis in horses and sheep.
Contains rumicine an irritant that mainly affects pregnant cows, calves and bullocks.
Field cases of toxicity are rare.
Symptoms:
Rumicine toxicity; incoordination, swaying of the hindquarters, inability to rise after falling, smelly faeces, dark urine and swelling of the bowels.
Oxalate poisoning.
Treatment:
Remove stock from the infestation.
Rumicine toxicity; 250-500 g Epsom salt drench.
Oxalate poisoning.
Legislation:
Noxious weed of TAS and 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.
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.
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:
A number of biocontrol agents have been tested and some released in Australia.
Related plants:
Bladder Dock (Rumex vesicarius)
Broadleaf Dock (Rumex obtusifolius)
Clustered Dock (Rumex conglomeratus)
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)
Swamp Dock (Rumex brownii)
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). P208-209. Photo.
Black, J.M. (1965). Flora of South Australia. (Government Printer, Adelaide, South Australia). P280-281. Diagram of seed.
Burbidge, N.T. and Gray, M. (1970). Flora of the Australian Capital Territory. (Australian National University Press, Canberra). P153, 155. Diagram of seed.
Cunningham, G.M., Mulham, W.E., Milthorpe, P.L. and Leigh, J.H. (1992). Plants of Western New South Wales. (Inkata Press, Melbourne). P234-235. Photo.
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). P200-201. Photo.
Hyde-Wyatt, B.H. and Morris, D.I. (1975). Tasmanian weed handbook. (Tasmanian Department of Agriculture, Hobart, Tasmania). P54-55. Diagrams.
Hyde-Wyatt, B.H. and Morris, D.I. (1980) The Noxious and Secondary Weeds of Tasmania. (Tasmanian Department of Agriculture, Hobart, Tasmania). P66-67. 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). #1072.5.
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). P116.
