Report of a study visit to mountain cloud forest in the state of Rio de Janeiro, Brazil
By Dusha Hayes (R.B.G. Kew Orchid Unit)
In October 1991, I was sponsored by the Stanley Smith Trust, R.B.G. Kew, Kew Guild and the R.H.S. to go on a study visit to the Mountain Cloud Forest in the state of Rio de Janeiro, to study orchids growing in their natural habitat.
My visit was arranged by Dr. Richard Warren, of Equatorial Plants Co. in Edinburgh. My guide and host in Brazil was David Miller, Dr. Warren’s partner. The property, consisting of two sites, Sitio Bacchus and Sitio Sophronitis, is part of “Mata Atlantica Conservation Project”. This project is financed by Shell Oil, the National Research Council and the Macarthur Foundation. Further support is given by the local municipality, the Pro-Natura Environmental Research Institute and by David and Isabel Miller. The site is also used by a group of botanists from Rio de Janeiro Botanic Garden for research work on native trees and shrubs.
Sitio Bacchus is located some 100 miles north of Rio de Janeiro and four miles from Nova Friburgo, the nearest town. It covers approximately 1,000 acres, with boundaries well defined by mountain ridges rising from 1,000 to almost 2,000 metres above sea level.
On a small hill near the house at Sitio Bacchus is the “Intensive Care Unit” where the plants that need special care are kept; plants that have been picked from fallen trees or ones knocked down in storms.
Here we carried out a survey of Laelia crispa re-establishment and seedling distribution. The mature plants of Laelia crispa were brought from the Pireneus Valley over a period of 14 years, hand pollinated and the seeds allowed to spread naturally to assess their capability for re-establishment. However the main conclusion of the survey was that the seeds do not germinate far from the parent plant but favour the area around its root system. So Laelia crispa is a species which is as endangered as its original forest environment.
Besides Laelia crispa there were many epiphytic orchids growing here – Miltonia cuneata, Pleurothallis sclerophlla, Pleurothallis miersii, Pleurothallis handroi, Bifrenaria atropurpurea, several Stelis sp. and Barbosella sp.
There are eight walks which criss-cross the property. They are of varying difficulty and take from two to five hours. Walk 1 is situated in the part of the forest that was burnt about 30 years ago. This is now regenerating and has the characteristics of a mountain field – warm, dry and light. This is what David calls “Zygo” country. Here we saw Zygopetalum crinitum growing terrestrially. There were a few colonies doing quite well, but we saw many plants which were beginning to suffer. Normally these plants grow epiphytically as they need light to flower well. Here, as the forest regenerates, it is getting too dark for them, so only those in the tree tops survive.
We saw a lot of orchids along this trail such as Encyclia vespa, Encyclia calamaria, Grobya amherstiae, Pleurothallis sclerophylla, Pleurothallis pectinata, Laelia virens, Laelia cinnabarina, Gomesa crispa, Oncidium marshallianum, Oncidium forbesii, Maxillaria ubatubana and Maxillaria cerifera.
As elsewhere there were many gesneriads, aroids, bromeliads, begonias, ferns and dwarf mountain fuchsias.
In comparison to Walk 1, Walk 2 is situated in the part of the forest that regenerated much quicker than along Walk 1. Here the forest was warm, dark and humid, David’s “Colax” country. Consequently we saw several colonies of Colax (Pabstia) jugosa, various species of Stelis, Pleurothallis, Cirrhaea dependens, Epidendrumkleuppelianum, Bulbophyllum camposportoi, Oncidium hookeri and Oncidium crispum.
The other walks were similar but on Walk 7 we saw a lot of Sophronitis coccinea. It was the end of their flowering season, so only the ones quite high up in trees were still in flower. Some were in pod, which means that their natural pollinators were nearby. The top of this walk is 1,700 metres above sea level.
One week was spent at the second site, Sitio Sophronitis. Sitio Sophronitis is situated some 10 miles southeast from Sitio Bacchus in the Rio dos Flores valley. (The Flowers River Valley) The Flores River is well named as the river’s moss covered boulders are host to a red flowering gesneriad.
As in all tropical and sub-tropical rain forests the variety of plant life in general and the exuberance of epiphytic plants in particular, are striking features. More than 180 species of epiphytic orchids have been identified in the valley. There are also myriads of unidentified micro-orchids here, while from August to November the ridges and high tree branches simply glow with the flowers of scarlet Sophronitis coccinea, so giving the name to the site.
Two outstanding trails still live with me; one by the “Flower River” and the other a long and strenuous climb to the spectacular mountain peak, “Pica de Bicuda” some 1 ,600 metres above sea level.
Along the river we saw several colonies of gesneriads and Pitcairnia in flower and, half-way up “Bicuda”, on a tract of bare rock face we discovered a large colony of Maxillaria species.
One day was spent in the Pireneus Valley, the original home of Laelia crispa used in our re-establishment project. Efforts were being made to add this valley to the conservation area. Although many trees here have been cut down over the years, we found three large trees that have been spared, with colonies of Laelia crispa still growing happily.
During my visits to both sites we saw about 90 different species of orchids in flower.
At the end of the study visit three days were spent at two large local orchid nurseries, Binot’s and Floralia and at Rio Botanic Garden.