Bougainvillea

Bougainvillea glabra
infestation in bushland on Mount Coot-tha in Brisbane (Photo: Sheldon Navie)
shrubby habit (Photo: Sheldon Navie)
climbing habit (Photo: Sheldon Navie)
habit growing on a fence (Photo: Sheldon Navie)
close-up of stem showing the slightly curved thorns (Photo: Sheldon Navie)
leaves (Photo: Sheldon Navie)
showy branched flower clusters (Photo: Sheldon Navie)
the flowers are borne in three-flowered units along with three purplish bracts (Photo: Sheldon Navie)
close-up of the underside of the persistent floral bracts (Photo: Sheldon Navie)
young plant growing from a sucker (Photo: Sheldon Navie)
Vine
Alternate
Simple
Purple
Green

A rambling shrub or high-climbing woody vine. Its thick stems are mostly hairless and bear slightly curved spines (5-15 mm long) in the leaf forks. Its alternately arranged leaves (4-13 cm long) are shortly stalked with entire margins and pointed tips. Its small flowers are arranged in three-flowered units, with each flower being subtended by a large purplish bract (2.5-5 cm long). These flowers have a greenish or purplish tube (9-20 mm long) with five small cream, yellowish or whitish 'petals' at the tip.

Common names 
Also known as: Bougainvillea, lesser Bougainvillea, paper flower,
Family 
Nyctaginaceae
Deciduous 
No
Flowering time 
Autumn
Native/Exotic 
Exotic
Origin 
Native to Brazil.
Notifiable 
No
Council declaration 
SIL – Special Investigation List
Known distribution 

Occasionally naturalised in south-eastern Queensland (i.e. in the Moreton and Darling Downs district). Also naturalised in the coastal districts of central and northern Queensland and on Lord Howe Island. Possibly also naturalised in south-western Western Australia.

Habitat 

A minor weed of riparian vegetation, open woodlands, coastal environs, old habitations and gardens, roadsides, railway lines, disturbed sites and waste areas.

Habit 

A rambling, vine-like, shrub (i.e. scandent shrub) or high-climbing woody vine.

Impact and control methods 
Stem and leaves 

The stems are relatively thick and bear slightly curved spines (5-15 mm long) in the leaf forks (i.e. axils). These branches are usually hairless (i.e. glabrous), but they may occasionally be sparsely hairy (i.e. puberulent). Older stems eventually become woody with deeply-fissured bark. The alternately arranged leaves are borne on stalks (i.e. petioles) 3-10 mm long. These leaves (4-13 cm long and 1.5-6 cm wide) are egg-shaped in outline (i.e. ovate), heart-shaped (i.e. cordate) or slightly elongated (i.e. narrowly ovate) with entire margins and pointed tips (i.e. acute apices). Their upper surfaces are hairless (i.e. glabrous), while their undersides are sparsely hairy (i.e. sparsely pubescent).

Flowers and fruits 

The small whitish flowers are arranged in three-flowered units in the upper leaf forks (i.e. in axillary three-flowered cymes), with each flower being subtended by a brightly-coloured, persistent, bract. These flower-units may also be grouped into larger branched clusters at the tips of the branches (i.e. terminal panicles). The showy flower bracts (2.5-5 cm long and 1.5-4 cm wide) are purple or magenta in colour and are joined to the flower stalks (i.e. adnate to the pedicel). The individual flowers have a greenish or purplish tube (i.e. perianth tube) 9-20 mm long with five small cream, yellowish or whitish 'petals' (i.e. perianth lobes) about 2.5 mm long at the tip. These flowers have 6-8 stamens borne on stalks (i.e. filaments) 8-13 mm long and an ovary topped with a very short style (about 1 mm long) and feathery stigma about 2.5 mm long. This species does not produce fruit in Australia.

Reproduction and dispersal 

Bougainvillea (Bougainvillea glabra) only reproduces vegetatively in Australia, either by suckering or layering (i.e. its stems produce roots when they come into contact with the soil).Plants spread laterally over time, eventually forming large and dense thickets. They also become established in bushland after being dispersed in dumped garden waste.

Similar species 

Bougainvillea (Bougainvillea glabra) is very similar to great bougainvillea (Bougainvillea spectabilis), which is present in cultivation in the region. These two species can be distinguished by the following differences: bougainvillea (Bougainvillea glabra) has hairless (i.e. glabrous) or sparsely hairy (i.e. puberulent) stems and leaves, and typically has purple or magenta floral bracts that are about as long as the flowers.great bougainvillea (Bougainvillea spectabilis) has hairy (i.e. pubescent) stems and leaves, and typically has bright red, brick red or reddish-purple floral bracts that are longer than the flowers.