The African cherry

The African cherry (Prunus africana) is a large tree that lives only in montane areas of Africa. What does montane mean? A montane habitat is found in tropical areas, where a mountain has its foothills in a rainforest and as you go higher in elevation, the habitat gets colder, windier, and has more intense solar radiation. One interesting feataure is that montane forests look remarkably like the forests in my home state of Wisconsin. This is because as you go higher, plants and animals faced similar challenges in colder northern climates. But I digress.

About 40 years ago, the bark extracts from the African cherry were found to be effective in the treatment of enlarged prostates. Harvesters peel the bark off the tree and the species has the unusual ability to regrow its bark, as long as it is harvested gently. The bark is shipped all over the world where the extracts are made into capsules sold under its old scientific name, Pygeum. You can find it in any health food store and it can be found in formulations with saw palmetto, which is used for the same purpose.

So much of the bark has been harvested that the species was included in the Convention of International Trade in Endangered Species (CITES) Appendix II. This means that licensing is required of exporters and importers and the trade must be monitored. In 2000, a bark extraction factory (owned by the French company, Groupe Fournier) called Plantecam closed its doors because of reduced harvesting quotas on Mount Cameroon, business and political decisions in France and Cameroon, competition from other exporters, and depletion of the resource in another part of Cameroon, Called the Bamenda Highlands.

It may seem surprising but until I started my study, no one determined sustainable harvest levels. Except for the harvest quotas on Mount Cameroon, no one ever looked at the effect of harvest on populations of trees or even on individual trees. From the very beginning, the harvest was known to be destructive. Although many trees recover from removal of its bark, at least half eventually die. The question of sustainability is the focus of my study on Mount Oku, the location of one of largest remaining populations in Cameroon.