17 YEARS AGO
Sour prickly pear has a negative economic impact for landowners as it renders viable grazing and agricultural land useless. Here are some tips on how to get rid of it.
Sour prickly pear invades dry savanna and spreads primarily by seeds, and secondly by vegetative means.
Fruits are eaten by many animals, mainly baboons, monkeys, antelope, birds and elephants.
Humans are the main distributors of the weed, as they are often planted in gardens from where they spread.
Full name: Australian pest pear, sour prickly pear, suurturksvy, or Opuntia stricta.
Origin: Florida, United States. Description:
• Spreading, highly branched succulent shrub (0,5m to 1,5m high). • Cladodes are green to blue-green and flattened (longer than broad). • Spines are up to 40mm long, usually one or two in a group or absent.
• Flowers are yellow and showy (introduced as an ornamental), up to 70mm long. • Club-shaped fruit are red, turning purple outside and inside, an important identification feature (the deep-purple juice is often used as a food colourant).
Flowering takes place from November to January.
Prickly pear is controlled effectively by a newly introduced, hostadapted biotype of cochineal. For dense infestations, only biocontrol is effective. Ensure that the stricta biotype of the prickly pear cochineal is present in every infestation of the Australian pest pear. Contact your provincial office of the Directorate of Agriculture, Land and Resource Management to establish where the nearest cochineal-infested leafpads are, and carefully place these into the centre of the plant infestation (where they will be protected from wind and rain).
Once the insects have started to multiply, their dispersal can be accelerated by carrying the infested leadpads to distant plants.
No chemical control is required once cochineal has been established in all areas where Australian pest pear is present.
Before applying herbicides, it is important to read instructions carefully.
RIGHT: Thesourprickly pearisaninvasive speciesthatcan renderagricultural landuseless. This photograph accompanied the article in our 19 October 2001 issue.