Stellenbosch University Botanical Garden, South Africa

Common name: buchu

Family: Rutaceae (Rue)

Distribution: Western Cape: Cederberg to Groot Winterhoek Mountains including the Piketberg

Habitat: Fynbos, rocky sandstone slopes 300-700m ASL

National red list: Least Concern

Life form: Evergreen shrub / sub-shrub

Comments: One of the Cape's most important medicinal plants, with a long history of traditional use, especially as a herbal medicine to treat urinary tract infections and prostatitis. It is simultaniously diuretic, antispasmodic and disinfectant, making it particularly suitable for these uses.
The largest modern application of the buchus Agathosma betulina and A. crenulata is in the flavour and fragrance industry where the two commercially used buchu species are used to enhance fruit flavours, especially to boost black currant-like flavours. The fragrance includes minty camphoraceous, sweet berry, catty, tropical guava, apricot and peach, green herbal notes. The oil is also used in perfume and cologne.
Both the active medicinal, flavour and scent compounds are within the conspicuous oil glands dotting the bottom of the leaves, as is typical for all plants in the citrus family.
Until 1995, the only sources of buchu were wild populations in the mountains of the Western Cape. Althpugh now commercially grown, it is still impacted through out its range by wild harvesting for essential oils and medicinal trade. Prices between 1998 and 2004 were very high due to demand from overseas markets. Although not well documented it is suspected that ongoing sustained harvesting pressure on wild subpopulations has caused decline in the number of individuals. However harvesting is not neccesarily destructive as only leaves and branches are cut. This species is a multistemmed resprouter normally able to recover from moderate harvest pressure. Only repeated severe harvest is likely to cause population decline. Since 2006 legislation has been established to favour cultivated material and reliance on wild harvested material has declined substantially. At 2016 it was estimated that decline in the population is not expected to be over 10%.