Cutleaf Mignonette

Reseda lutea L.

Family: - Resedaceae.

Names:

Reseda is from the Latin resedare meaning to calm and refers to its herbal properties as a sedative.

Lutea is from the Latin luteus means yellow and refers to the flower colour or saffron yellow dye extracted from the plant.

Cutleaf Mignonette refers to the deeply divided or cut leaves and Mignonette is from the French mignon meaning small and delicate and probably refers to the flowers.

Other names:

Wild Mignonette (UK)

Yellow Mignonette (USA).

Summary:

An erect, bushy, almost hairless plant to 1 metre tall, with deeply lobed leaves and leafy stems ending in a long, yellow flowering spike from November to December. It has annual tops with an annual to short lived perennial rootstock

Description:

Cotyledons:

Two. Oval. Tip round. Sides convex. Base tapered. Hairless. Petiole about the same length as the blade.

First Leaves:

Oval, round tipped. Hairless.

Leaves:

Alternate. Forms a rosette that withers before flowering.

Petiole - Lower ones often with a petiole(leaf stalk).

Blade - Dark green, mainly 3-5 lobed or with deeply divided leaflets, pointed tip, edges smooth and wavy. Withering early. Hairless.

Stem leaves - 50-100 mm long, usually with 3 narrow lobes, becoming smaller and less lobed towards the top. Lobes almost to the midrib, acute tipped, oblong, smooth and wavy edged. No petiole.

Stems:

Many, erect, stiff, slender, 300-1000 mm tall, lengthwise ribbed. Branched from the base and along their length . Woody base. Scattered hairs or hairless.

Flower head:

On the ends of the main stem and upper branches in spike like racemes, 100-200 mm long that become longer when in fruit. Flowers in closely packed clusters on short stalks.

Flowers:

Pale yellow, irregular, bisexual.

Bracts - Small

Ovary - Superior. Attached on a fleshy disk. Single celled carpels.

Sepals - 6, parallel sided. Fall off with age.

Petals - 6, yellow-green, somewhat rough to touch. 2 upper petals with a broad claw and 3 lobes with the 2 side lobes being crescent shaped with tiny rounded teeth on the outer edge and the centre lobe being parallel sided and shorter. The 4 remaining petals are tiny.

Stamens - 12-20 attached to a fleshy disk.

Anthers -

Fruit:

Oblong, erect, angular 8-12 mm long capsule with 3, incurved, short, pointed teeth(beaks) and 3 openings on top. Contracted below the top. Many seeds per capsule.

Seeds:

Small, brown to black, smooth, shiny, kidney to egg shaped, 1.7-2 mm diameter, no seed coat(albumen). Embryo curved.

Roots:

Deep, to 800 mm, yellow-brown, branched taproot with many almost horizontal and branched laterals.

Key Characters:

Leaves divided.

Sepals 6.

Petals 6.

Capsule 3 toothed.

From J.M Black and B.L. Rye.

Biology:

Life cycle:

Annual, biennial or short lived perennial herb. Germinates mainly in autumn and forms a and a deep taproot and a rosette of leaves that grow through the winter. The rosette leaves wither as the flowering stem(s) emerge in spring. Flowers are normally formed from October to December. A minor germination may also occur in spring and this does not usually flower until the following spring or summer. The flower stems die off in late summer and a new rosette of leaves is formed in autumn. Depending on the area the plants may die after their second flowering or survive for a number of years.

Physiology:

Reproduction:

By seed and perennial rootstock.

Flowering times:

Summer in SA.

Late spring in WA.

Seed Biology and Germination:

Seeds germinate over several months in the field.

Fresh seed won't germinate for a few weeks.

Optimum temperature for germination is around 250C.

About 30% of seed is dormant and this dormancy can be broken by scarification.

Emergence can occur from 80 mm deep.

Seedlings sensitive to competition.

Vegetative Propagules:

Perennial rootstock.

Hybrids:

Allelopathy:

Population Dynamics and Dispersal:

Spread by seed mainly by water, road making, as a contaminant of agricultural produce, on vehicles and by animals.

A few seeds survive passage through the gut of animals.

Cultivation appears to assist its spread. Root fragments may re shoot after being spread by cultivation if the weather is mild.

Seedling mortality is normally high, but once established it can withstand repeated defoliation.

Origin and History:

Mediterranean. Europe. Asia minor.

Probably introduced in the early 1800's.

First recorded as naturalised in NSW in 1902.

Naturalised in SA in 1913.

Distribution:

NSW, SA, TAS, VIC, WA.

Habitats:

Exposed, disturbed areas.

Climate:

Temperate. Mediterranean.

Soil:

More abundant on the drier, sandy or gravelly calcareous soils and chalky loams.

Plant Associations:

Significance:

Beneficial:

Formerly cultivated to produce a yellow and green dyes for cotton, silk, linen, wool and 'Dutch Pink' paint. Blue green and yellow dyes were extracted.

Oil used in perfumes.

Used in herbal medicine.

Detrimental:

Serious weed of vegetables.

Weed of crops, cereals, vegetables, seedling lucerne, potatoes, sugar beet, carrots, pastures, fire breaks, fallows, roadsides, riverbanks and disturbed land.

Hosts cabbage root fly and water melon mosaic virus in Europe.

Toxicity:

Not recorded as toxic.

Legislation:

Noxious weed of SA and TAS.

Management and Control:

Cultivation, herbicides and competitive pasture species generally give good levels of control.

Slashing and mowing are not very effective because the plant re-shoots from the base.

Heavy grazing kills seedlings.

Hormone herbicides are effective on young plants.

Atrazine and sulfonyl urea herbicides provide good control.

Thresholds:

Eradication strategies:

Manually remove isolated plants.

Cultivate larger areas regularly.

Herbicide resistance:

Biological Control:

Related plants:

Wild Mignonette (Reseda luteola) has undivided leaves.

Scented Mignonette (Reseda odorata) is an ornamental plant.

White Mignonette (Reseda alba) has white flowers.

Plants of similar appearance:

References:

Black, J.M. (1965). Flora of South Australia. (Government Printer, Adelaide, South Australia). P389.

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). P206-207.

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). #1047.2.

Parsons, W.T. and Cuthbertson, E.G. (1992). Noxious weeds of Australia. (Inkata Press, Melbourne). P558-561. Diagram. Photos.

Wilding, J.L., Barnett, A.G. and Amor, R.L. (1987). Crop weeds. (Inkata Press, Melbourne). P142. Diagrams. Photos.

Acknowledgments:

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