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PRICKLY PROBLEM
23/02/2023

There has been concern about this plant in Southern France and other southerly areas of Europe for some time. It has been spreading on the slopes in our area of the arrière-pays of the Alpes Maritimes for several years and is now rapidly invading Switzerland. It is a large cactus familiar to many who collect cacti and succulents as the prickly pear. The fruits of some species are edible, hence the “pear” epithet of the vernacular name, but they are tricky to prepare and gloves need to be worn to protect the hands from the tine spines that are contained in the glochids all over the fruit.

The flowers and the fruit are exotic and attractive but this beauty conceals the invasive nature of the plant, which is resistant to cold temperatures and spreads rapidly from the spiny pads which break away easily from the parent plant. They are very difficult to eliminate and require specialist equipment and protective clothing to remove. Even when they are removed, they regrow/recolonise quickly so that control rather than elimination is probably the most that can be achieved for now in many places. Biological controls are being developed and the cactus moth Cactoblastis cactorum (Berg, 1885) is one that has had success in Australia, South Africa and elsewhere but it attacks other non-target species of ecological value so release is not necessarily a solution.
Botanically, these are cacti of the genus Opuntia in which there are well over 250 species and hybrids. They are native to the Americas but have spread far and wide.

As far as I know they have not entered the wild in the UK yet, but even in our wet climate, with global warming, their ability to colonise, resistance to cold and prickly armour, who knows? I do have one (safely away from the wild) which, as you can see from the photo below, obviously loved me!
Betts Ecology keeps a wary eye open for invasive exotic species and we will eliminate those we find that are a threat to native vegetation and biodiversity. If you think you have spotted invasive species on our sites, let us know and we will check it out.
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