Orchidaceae

Big ORCHID Fernkloof HEADER

Orchids, numbering about 26 000 species, comprise the largest family of flowering plants worldwide. South Africa has close to 500 species, about 90% of which are terrestrial (growing on the ground) others are epiphytic (growing on trees or shrubs). There are 241 species in the Cape Floral Region, an unusually high number for a temperate region. Fernkloof Nature Reserve has recorded 81 species.

Response to fire

Many terrestrial orchids in the fynbos biome have adapted to fire by flowering only in the first year after a fire. By so doing these orchids gain the advantage of seeding into an environment that is relatively free from competition by other plants.
A few species, such as Disa ferruginea and Disa graminifolia, are not fire-dependent and will flower in mature fynbos vegetation.

Pollination

Pollinators have been documented for more than 100 South African orchid species.

Bees, such as carpenter bees, blue-banded bees, leaf-cutter bees and oil-collecting bees are some of the most important pollinators. Other pollinators include spider-hunting wasps, flies, scarab beetles and moths. Many orchids lack nectar in their flowers and have evolved to mimic other flowers or even insects to attract pollinators.
A few species of orchid such as Disa glandulosa, Disa bracteata and Disa vaginata self-pollinate.

Orchids in Fernkloof Nature Reserve

Fernkloof Nature Reserve has 81 species of orchid.

An extremely exciting discovery for the Hermanus Botanical Society, for Fernkloof and for the orchid world in general, was the rediscovery in 2016 of Disa forficaria, an orchid last seen in 1966 near Houwhoek in the Groenland Mountains.
It was first discovered by Johann Drege in 1826 near Worcester.

Post-fire monitoring

During the first one to three years after a fire, members of the Hermanus Botanical Society monitor the regrowth in the Reserve and compare with fires from previous years.

Orchid species are recorded, photographed and many are tagged with a GPS reading.
Information on rare and endangered orchids is sent through to CREW (Custodians of Rare and Endangered Plants) at the South African National Botanical Institute and entered into their Threatened Species database.

References:

  • The Cape Orchids; William R. Liltved, Steven D Johnson
  • Orchids of South Africa; A Field Guide; S Johnson, B Bytebier, H Starker