Opuntia stricta (erect prickly pear).
Opuntia stricta is a cactus species native to the Americas that has been introduced worldwide as a popular ornamental. This species escaped from cultivation and has become invasive in many countries across Africa and Australia, but also more recently in the Mediterranean basin. Large and serious invasions have been reported in Australia, South Africa, Namibia, Yemen, India, Sri Lanka, Madagascar and lately also Spain and some North African countries. It has also become naturalized in many other regions (primarily in Africa and Asia) where it has not yet been recorded as a pest. In South Africa and Namibia large infestations have been reported, mainly in dry savanna bushlands, while in Australia all states are invaded with widespread populations invading southeastern Queensland and northeastern New South Wales. Successful biological control programmes have, however, severely reduced the spread of this species in many areas where introduced, though there continues to be a risk of further introduction through the nursery trade.