A trailing or climbing, annual, almost hairless, leguminous vine with blue pea type flowers and leaves that end in branched tendrils and have 2-5 pairs of leaflets.
Description:
Cotyledons:
Two. Below ground. Hairless.
First leaves:
Have only one or two pair of elliptical leaflets with no stipules.
Leaves:
Alternate. Does not form a rosette. 2-6 pairs of leaflets terminating in a simple or forked tendril.
Stipules - Parallel sided and smooth edged on upper leaves.
Petiole - Yes.
Blade - 8-12 mm long by 5-11 mm wide, parallel sided.
Stems:
Slender, twining, up to 700 mm long. Square with lengthwise ridges. Branch from the base.
Flower head:
1-3 flowers in upper leaf axils on a thread like stalk(peduncle) about as long as the leaf.
Flowers:
Pale blue/mauve pea-type flowers.
Ovary - Style thread like, bearded in upper part.
Calyx - Half as long as the corolla. Teeth of different lengths.
Petals - -Blue to pale purple or lilac, 4-6 mm long.
Stamens - 10, upper stamen free, other 9 united in an open tube, staminal tube oblique at summit.
Anthers -
Fruit:
Flattened, hairless, round tipped, 4 seeded pod, 10-14 mm long by 4 mm wide, 2 valved, dehiscent, on a short stalk. Not breaking transversely into articles.
Seeds:
Roots:
Taproot with nitrogen fixing nodules.
Key Characters:
Weak climbing herb.
Leaves divided into 2-6 pairs of leaflets, paripinnate, terminating in a simple or branched tendril.
Stems terete to angular.
Flowers small, 4-6 mm long, very irregular(zygomorphic), petals unequal, more or less united, the upper one(standard) outside the others in bud.
Flowers in racemes on long peduncles.
Style filiform, bearded in upper part.
Stamens 10, upper stamen free, other 9 united in an open tube, staminal tube oblique at summit.
Pod compressed, 4 seeded, short, 2 valved, dehiscent, not breaking transversely into articles.
Embryo curved.
From J.M. Black.
Biology:
Life cycle:
Annual. Seed germinates autumn to winter. Flowers in spring.
Physiology:
Fixes nitrogen.
Reproduction:
By seed.
Flowering times:
November to December in SA.
Seed Biology and Germination:
Vegetative Propagules:
None.
Hybrids:
Allelopathy:
Population Dynamics and Dispersal:
Spread by seed.
Origin and History:
Europe. Western Asia. North Africa.
Distribution:
ACT, NSW, QLD, SA, TAS, VIC, WA.
Habitats:
Climate:
Temperate.
Soil:
Plant Associations:
Significance:
Beneficial:
Detrimental:
Weed of other roadsides, crops, gardens, cultivation and disturbed areas.
Toxicity:
Not recorded as toxic.
Legislation:
None.
Management and Control:
Thresholds:
Eradication strategies:
Prevent seed set for 5 years by grazing, mowing, pulling or applying herbicides.
Hand spray with 1 g of chlorsulfuron(700g/kg) plus 25 mL wetting agent in 10 L of water or boom spray with 20 g/ha chlorsulfuron(700g/kg) in autumn to early winter each year. Hand pull survivors in spring before seed set.
For small infestations and in grass dominant areas an annual application of 10 mL Tordon®75-D in 10 L water in early winter gives excellent control of existing plants and has residual activity to control seedlings.
In bushland, 200 g/ha Lontrel®750 or 50 g/ha Logran® applied in early winter provides reasonably selective control. For hand spraying use 25 mL wetting agent plus 4 g Lontrel®750 or 1 g Logran® in 10 L water. Repeat annually for several years.
Plant tall growing perennial species to reduce re-invasion.
Metsulfuron also provides good control but is less residual and less selective. It is relatively tolerant to glyphosate.
Herbicide resistance:
Biological Control:
Related plants:
Broad Bean (Vicia faba var. major)
Common Vetch (Vicia sativa ssp. sativa) has leaves are divided like a feather into 3-10 pairs of small narrow leaflets, each 8-30 mm long. It has pink to purple pea flowers, each 10-20 mm long and either single or in few-flowered clusters. The seed pod is narrow, slightly flattened and 30-50 mm long.
Hairy Vetch (Vicia hirsuta) has an elongated inflorescence of several small flowers each only 2-3 mm long and small, 6-9 mm long hairy seed pods.