T.E.R:R.A.I.N - Taranaki Educational Resource: Research, Analysis and Information Network


Dipogon lignosus (Mile-a-minute Vine)

Kingdom: Plantae
(Unranked): Angiosperms
(Unranked): Eudicots
(Unranked): Rosids
Order: Fabales
Family: Fabaceae
Subfamily: Faboideae
Tribe: Phaseoleae
Subtribe: Phaseolinae
Genus: Dipogon
Species: D. lignosus
Binomial name: Dipogon lignosus
Common name: Mile-a-minute Vine, Sweet pea vine, Pea vine, Cape Sweet Pea, Dunny vine, Dolichos pea.

Dipogon lignosus is a vigorous herbaceous leguminous perennial climbing vine originating from South Africa. In Australia and New Zealand this plant has become a highly invasive weed, climbing into and smothering trees and shrubs, as well as spreading sideways and covering large areas of ground and ground cover plants. It is now found throughout the North Island of New Zealand including Taranaki. It inhabits wasteland, forest margins, stream banks, roadsides and it favours sheltered shaded areas. It increases nitrogen in impoverished soil types, potentially changing the species that can grow there.

Dipogon lignosus has slender, twining stems up to 4m long which become rope like with age. The long stalked leaves are smooth, medium green and pale below. Each leaf consists of 3 tapering leaflets (3- 9 cm ×=1- 7cm)
Its flowers are clusters of pea-like blooms, white, pale mauve to purple, are borne on stalks mainly between July, August, September, October, November, December, and January.

The seed pods are narrow and sickle shaped (2- 5cm long) with ovate, black seeds, (up to 4.5mm long). Once ripe, the seed is explosively flung out of the pod, falling far from the parent plant. These seeds can also be spread via water (fresh and sea), birds and spread in dumped vegetation or soil. Seeds can remain dormant for a number of years in unfavourable conditions, only germinating once ideal conditions occur.

The Latin word lignosus means woody, and refers to the woodiness of the stems at the base of the plant. Dipogon is from the Greek di, meaning two, and pogon, a beard, referring to the style which is thickly bearded on the upper side near the tip.

For more details all photos will enlarge on clicking.




 

The three tapering leaflets
 

The topside of a leaflet.
 

Underside of a leaflet.