drooping tree pear

Opuntia monacantha syn. O. vulgaris
Succulent
Alternate
Reduced / Needle
Yellow
Green

Drooping tree pear is a succulent shrub or tree growing to 5m in height often having a definite trunk that is much branched at the top and has drooping upper branches (cladodes). Branches are narrowly obovate (egg-shaped in outline but with the narrower end at the base) to oblong-lanceolate; base somewhat tapered (cuneate), 10-35 cm long, 7.5-12.5 cm wide. Succulent branches bear areoles with 1-3 grey or yellowish to reddish brown spines with darker tips, while the trunk areoles have 10 or more spines.

Common names 
Also known as: drooping prickly pear, barbary fig, cochineal prickly pear, common prickly pear, drooping pear, smooth tree pear, spiny prickly pear, spreading prickly pear,
Family 
Cactaceae
Deciduous 
No
Flowering time 
Late spring to early autumn
Native/Exotic 
Exotic
Origin 
South America
Notifiable 
No
State declaration 
Category 3 - Must not be distributed or disposed. This means it must not be released into the environment unless the distribution or disposal is authorised in a regulation or under a permit.
Council declaration 
As per State Declaration
Known distribution 

This species has a very widespread distribution in Australia, however it is not particularly common. It is scattered in northern and south-eastern Queensland, eastern New South Wales, south-eastern South Australia, south-western Western Australia and Victoria. Also present in other parts of Queensland and New South Wales

Habitat 

Moist savanna and coastal scrub also, agricultural areas, coastland, ruderal/disturbed sites.

Habit 

Erect shrub to two metres tall, sometimes with a short trunk. Plant has an obvious drooping appearance.

Impact and control methods 

Drooping tree pear (Opuntia monacantha) is regarded as an environmental weed in Queensland, Victoria and Western Australia.

Stem and leaves 

The stems are bright green and much-branched, but with a single thick woody trunk at the base. These stems consist of a series of very flattened, oblong to egg-shaped (i.e. obovate), fleshy (i.e. succulent) segments. These segments (10-45 cm long, 5-15 cm wide and 4-15 mm thick) are hairless (i.e. glabrous) and somewhat glossy in appearance. They are covered in small raised structures (i.e. areoles), some of which bear 1 or 2 long spines (2-7 cm long). Some of the uppermost stem segments droop towards the ground, particularly when in they are covered in fruit.
The leaves are reduced to tiny cylindrical (i.e. terete) or cone-shaped (i.e. conical) structures (2-3 mm long). These leaves are quickly shed from the plant (i.e. they are caducous).

Flowers and fruits 

The showy flowers (7.5-10 cm long and 3-7.5 cm across) are borne singly on fleshy bases along the margins of the stem segments. These flowers are yellow with reddish-coloured markings on the undersides of the outermost 'petals'. They have numerous 'petals' (most of these are actually petal-like structures known as petaloids) that are 18-40 mm long and 12-40 mm wide. Flowering occurs mostly from late spring through until early autumn.
The immature fruit are green in colour, but turn purplish-red as they mature. These berries (4-7.5 cm long and 2-5 cm wide) are fleshy (i.e. succulent), rounded (i.e. globose) or somewhat pear-shaped (i.e. pyriform or obovoid), and have depressed tips. Several tufts of tiny bristles (i.e. areoles with glochids) are present on these fruit and the reddish-coloured pulp contains large numbers of smooth seeds. These seeds (3-4 mm across) are generally yellow or pale brown in colour and somewhat rounded (i.e. sub-globose) in shape.

Reproduction and dispersal 

This species reproduces by stem fragments (cladodes may become dislodged and produce roots) and also by seeds. Stem fragments may become attached to animals, footwear and vehicles. They are also dispersed by flood waters and in dumped garden waste. The fruit are eaten by various animals (e.g. birds and foxes) and the seeds then spread in their droppings.

Similar species 

Drooping tree pear (Opuntia monacantha) is very similar to spiny pest pear (Opuntia dillenii), common prickly pear (Opuntia stricta), Indian fig (Opuntia ficus-indica), white-spined prickly pear (Opuntia streptacantha) and velvety tree pear (Opuntia tomentosa).