Berries - not for eating

Himalayan Firethorn or Pyracantha crenulata is an invasive alien plant in our province so I was not surprised to see it when I went walking on Swartkops, it was one of many invasive plants growing on the hill. Initially introduced as a hedge plant, it has long sharp thorns and the seeds have been spread all over by birds which eat the berries. While they look like appealing, like little apples, the berries can cause stomach upsets in humans if eaten raw in large quantities.

These little red berries belong to an indigenous mistletoe, Viscum rotundifolium, related to European mistletoe species of the same genus. Birds are also the culprits in the spread of this parasitic plant. When the birds eat the berries and defecate the seeds, if they land on a tree, they germinate and grow into the tree, using the tree to supply water and soil nutrients. It is less damaging to the trees it lives on because it has its own green leaves, meaning that it makes its own food and it doesn't usually cause parts of the affected tree to die off. Although some types of mistletoe are used medicinally, this one is not. It is also not specific to certain trees, it is capable of parasitising a wide variety of hosts.