photographic guide to the epiphytic orchids of the ......apr 01, 2015  · available, the new orchid...

Photographic Guide to the

Epiphytic Orchids of the

Aberfoyle Estate,

Honde Valley,

Zimbabwe

Peter Ashton

P.O. Box 905-502

Garsfontein West, 0042,

Pretoria, South Africa

(E-mail: carolash@iafrica.com)

Version 1 – April 2015

A Brief Introduction to this Guide

The Aberfoyle Estate is one of a group of active tea-

growing estates that occupy the picturesque northern

(upper) end of the Honde Valley in the Eastern Districts of

Zimbabwe. The estate is situated on the lower, eastern

slopes and foothills of Mount Nyangani, the highest peak in

Zimbabwe, with wonderful views towards Mozambique.

Mount Nyangani receives relatively high rainfall during the

summer months of each year and many perennial streams

and rivers drain the slopes, flowing towards the

Mozambique border. Frequent mists occur during the drier

winter months, providing an additional source of moisture to

the lush vegetation of the area.

The hill slopes are covered with dense stands of tall, moist

tropical woodland and forest, and the many waterways are

lined with lovely stands of riparian forest. The array of forest

and woodland habitats provides a range of suitable

environments for epiphytic orchids, and also for a wide

variety of bird, reptile, amphibian and butterfly species.

Epiphytic orchids grow on trees and occasionally on rocks,

anchoring themselves to their host tree (or rock) by a

network of roots. The orchids do not derive any nutrition

from the host tree and obtain the nutrients they need from

wind-blown dust, decaying bark and bird droppings. The

roots of epiphytic orchids are also able to absorb moisture

from mist in addition to any rainfall that is received during

the summer months.

In this guide, the nineteen epiphytic orchids that have so far

been recorded at the Aberfoyle Estate have been arranged

in alphabetical order for convenience. Photographs are

provided for each species, and brief notes are given on the

key characteristics that will help to confirm the identity of

the species.

This photographic guide has been compiled with the aim of

helping visitors to Aberfoyle to identify the commonest

epiphytic orchids that have been found on the estate. As

more orchid surveys are carried out in the different habitats

on the estate, it is inevitable that more species will be

recorded from time to time. As this information becomes

available, the new orchid records will be added to this guide

so that it remains as complete as possible.

Additional useful information on the orchids of Zimbabwe

can be found in the following publications:

• Ball, J.S. (1978). The Epiphytic Orchids of Southern

Africa, edited by Jane Browning. Conservation Press

(Pty) Ltd, Johannesburg, South Africa.

• La Croix, I.F. & Cribb, P.J. (1998). Orchidaceae – parts I

and II. In: Flora Zambesiaca, Volume 11, parts 1 and 2,

edited by G.V. Pope. Royal Botanic Gardens, Kew.

The publications listed above are sometimes difficult to

obtain and a very convenient option is to use the Zimbabwe

Flora website (http://www.zimbabweflora.co.zw). This

website contains an enormous amount of information on,

and photographs of, Zimbabwe’s orchid flora as well as

other plant families found throughout the country.

Aeranthes parkesii

Angraecopsis parviflora

Bulbophyllum encephalodes

Bulbophyllum longiflorum

Bulbophyllum maximum

Bulbophyllum sandersonii

Bulbophyllum unifoliatum

Cyrtorchis arcuata

Cyrtorchis praetermissa

Jumellea wallerii

Microcoelia exilis

Oberonia disticha

Polystachya albescens

Polystachya cultriformis

Polystachya mauritiana

Polystachya transvaalensis

Rangaeris muscicola

Tridactyle bicaudata

Tridactyle tridactylites