Guides Corner

THE HIGHLAND TROPICS GALLERY
Entering the East Wing of the Conservatory, visitors will notice the temperature drops significantly in the Highland Tropics. Here, in the misty cloud forests of tropical mountaintops, hundreds of delicate orchids grow on the branches of gnarled trees. Dense mosses engulf rocks and ferns grow in abundance.

ARCHITECTURE/DESIGN/ARTWORK

• The center bed is five feet lower than the pathway. This was done to bring some variety to the floor area of the gallery. It's also a unique way to display the rather sprawling vireya rhododendrons allowing us a bird's-eye view of their trumpet-shaped flowers. In addition, this sunken bed provides a subtle way to separate valuable plants from visitors by growing the plants just barely out of reach.
• The large epiphyte tree, towering in the center of the sunken bed, was sculpted by the CemRock company. The seven moss-covered "trees" have a galvanized metal pipe core and are covered with long--fiber New Zealand sphagnum moss secured by stainless steel poultry wire and wrapped in sheet moss. All of the orchid-bearing branches on them are from California manzanita. These can be removed from the "tree" and the orchids and other epiphytes can be cared for in our back greenhouses.
• Dave Tuthill crafted the metal railing. He shaped the bars and rail with an "organic" feel about them. The flower motif is a stylized version of a Dracula orchid.
• The wooden orchid cases were made by Gene DeSmidt, of DeSmidt Design Build. Resembling Victorian armoires, these cases are made from ipé, a hardwood from Paraguay and Argentina. Ipé is extremely decay, pest and fire resistant. The wood is so dense and heavy that it sinks in water. This lumber was harvested from certified, sustainably managed forests.

GEOGRAPHY/CLIMATE/COUNTRIES
Countries with cloud forests include: Borneo, Colombia, Costa Rica, Ecuador, Indonesia, Malaysia, Mexico, Peru, Venezuela, Vietnam and Zaire. Most of the terrestrial plants in this gallery are from field-collected germplasm from Southeast Asia and Chiapas, Mexico.

• The plants in this gallery are found at 3,000-7,000 feet elevation in the mountains of the tropics. The Conservatory is one of only four public gardens in the United States to feature a highland tropics display. Others include the Cleveland Botanical Garden, Atlanta Botanical Garden and the Huntington Botanical Garden.
• These regions are sometimes referred to as "cloud forests" because they are often shrouded in mists and fog. The temperatures are much cooler in these regions than in the lowlands. Low cloudbanks form over the mountains such that the forest is actually immersed in clouds much of the time and the relative humidity is 100%.
• Large amounts of water condense on vegetation from clouds and light mist; the highest elevations of the forest are always dripping water from the leaves when shrouded in clouds.
• Cloud forest trees are covered in epiphytes, including orchids, mosses and filmy ferns. More than a thousand species of orchids have been found in the cloud forests of Peru alone. Most of the species in cloud forests are believed to be still unknown to science.
• Cloud forests play an extremely important role in the hydrology of tropical regions and watersheds. They capture, store, and filter water that feeds into local communities and large rivers hundreds of miles away.
• Cloud forests are especially vulnerable to global warming trends, because they rely on a combination of geographical and environmental factors that produce the misty and moist environment. Increasing temperatures would cause cloud lines to move farther up the mountain, reducing the area of cloud forests. In Monteverde, Costa Rica, where the cloud forest exists in a band only 1,000 to 1,300 feet in elevation, upward movement of the cloud line by even 165 to 330 feet would have a large impact. Local biologists have already noted that bird and bat species seem to be relocating their ranges upward, while amphibians that used to reside at the top of the mountain have disappeared altogether.
• Deforestation is also a severe threat to cloud forests. In the past, land has been cleared primarily for agricultural purposes, although development of housing and commercial enterprises could become an increasingly important factor in the future. The soil of cloud forests is generally quite fertile, but the topsoil layer is thin and is subject to rapid erosion once the forest is cleared because of the steep terrain. Decreasing soil quality causes farmers to resort to fertilizer and pesticide use, which creates a larger environmental problem because the cloud forest is often at the top of the watershed.
• A unique problem in some areas is that development to support the ecotourism industry has actually caused some additional damage to the forests themselves, or to other ecosystems and habitats that lie just beneath the edges of the cloud forests, where housing and supporting agriculture is likely to develop.

PLANTS

Epiphytes

• Epiphytes grow in highland and lowland tropics. We feature epiphytes in the Highland Tropics gallery because we have a renowned collection of high elevation ochids.
• "Epiphyte" comes from the Greek-epi translates to "upon" and phyton means, "plant." They can be found growing on the trunks, branches and even leaves of their host plant. They don't require soil structure for rooting, but rather rely on other plants for physical support often rooting into the suspended humus layer on tree branches. These are not parasitic plants and they do not typically harm the host plant.
• Primary vs. secondary epiphytes. Primary epiphytes start life high in the trees and have roots that grow down to the ground over time: ex. strangler fig. The fruits of the strangler fig are eaten by mammals who move through the canopy and deficate high in the trees. The strangler fig germinates there. Secondary epiphytes start life on the ground, use their roots to grow up trees, and can eventually dissociate from the ground: ex. philodendron.
• While they do indeed have access to sunlight growing atop trees and other plants, they also endure scorching temperatures and drying winds when the mists are absent. Since their roots never touch the water saturated soil, they have developed a number of strategies for collecting and storing water, not unlike those you'd see in a desert environment. These strategies include thick, waxy leaves to hold in moisture, succulent leaves and the thick pseudobulbs of some orchids that store water. CAM photosynthesis allows the plants to keep their stomata closed during the day, and to open them in the cooler temperatures at night to take in CO2. Epiphytes rarely lose their leaves because there is no way to regain the nutrients once they are dropped.
• Epiphytes can gather moisture from the air, capture and store water in spongy roots, and sometimes capture water in cups or pockets created by the structure of their leaves, the bromeliads are noted for this. Leaves and roots of epiphytes can trap dust and dirt, building up a "mat," or suspended humus layer, that holds moisture and nutrients.

• More than 70% of orchids are epiphytic. There are more than 15,000 species of epiphytic orchids in the tropics. Many of these plants are highly specialized with unique pollinators. This makes these plants particularly vulnerable to extinction due to habitat disruptions and destruction.
• Pleurothallidae:
  • This is a large tribe of orchids with more than 4000 species in almost 60 genera. They are native to the cool, high elevation cloud forests of South and Central America. The Conservatory has 50% of Pleurothallid genera. There are hundreds of Masdevallia spp., and we have about 33% of them.
  • Pleurothallids are non-pseudobulbous, and because of this, they cannot be allowed to dry out
  • These single-leaved plants have flowers that are dominated by 3 (usually colorful) sepals, with rather insignificant petals and lips. They often reflower from same inflorescence.
  • Dracula orchids have 3 petals at the center of each flower with the lower portion that moves and two "eyes." They have fleshy roots that absorb water and nutrients from the mist and suspended humus into which they grow roots.
  • They are typically pollinated by flies or gnats.
• Masdevallia species are mostly pollinated by flies. The hinged lip of some species is a pollination mechanism; the fly's weight triggers the labellum to slam against the column, leaving only a narrow tunnel for the fly to escape. Squeezing through the narrow passage, the flower deposits the sticky pollinia on the fly. Some of the odor compounds emitted by these flowers are not detectable by humans. Odor, not color, is what initially attracts the pollinators.
• Dracula species: The name is from the Greek word for "little dragon," in reference to the fanciful face-like image in the center of the flower, and not in reference to blood-sucking vampires. The dracula orchids feature an unusual hinged lip that swings back and forth to attract pollinators. Over 100 species are found in Central America and the northwest Andes, almost half in Ecuador alone.
• Stanhopea species: Native to Central and South America an Mexico. Insects don't visit for food; it is believed that male bees collect scent and convert it to sexual pheromones to attract females. Most stanhopeas have very specialized pollinator relationships; one or a small number of species pollinates a particular species. The pollinia must dry some (and so shrink) before being deposited on the stigma; this helps prevent self-pollination.
• Bulbophyllinae: This subtribe of epiphytes is pollinated by flies (carrion flies or nectar-seeking flies). The flowers are often dark red or brown with lighter spots, and a strong disagreeable odor. The flies are seeking carrion in which to lay their eggs, they mistake these flowers for carrion and in visiting, pollinate.

• Bromeliaceae has two growth forms (1)Vase: tightly overlapping leaves trap water (2) air plants with very hairy leaves that cause water to condense on them, which plants can then absorb. This plant family contains both pineapples and Spanish moss.
• The tightly overlapping leaves of these plants form vases or "tanks" where water is collected and held. Some of the largest bromeliads can hold as much as 5-1/2 gallons of water. These tanks can be complete ecosystems whose inhabitants include insects and small amphibians such as frogs.
• In this gallery you'll find plants growing on rocks as well. These are called "lithophytes."
• The Spanish moss, Tillandsia usneoides, that graces the displays in the Highland Tropics gallery is also a member of the bromeliad family. Note that it's neither Spanish nor a moss. Spanish moss does not have any roots. It uses its long, thin, scaly stems to wrap around the host tree and hang down from the branches. The leaves are covered with cup-like, permeable scales that "catch" moisture and nutrients from the air. This water-trapping ability allows Spanish moss to withstand long dry periods. In extreme dry spells, the plant becomes dormant until moisture returns.
• All members of the bromeliad family, but one, are native to tropical America and the West Indies. The exception is a single species of the genus Pitcairnia, which is native to Africa.

• Ferns have been in existence for more than 300 million years. They are a very diverse group. They grow in many different habitats around the world. There are about 12,000 species in the world today. In the highland tropics, ferns thrive on the high amount of moisture in the air. Some are terrestrial (such as tree ferns), some are epiphytic, some are lithophytes (growing on rock).

• After flowering plants and ferns, mosses are the most diverse group of plants, with more than 10,000 species in 700 genera. This makes mosses almost twice as diverse as mammals.

• Australia and Polynesia
• Staghorns are epiphytic ferns that grow in clusters on branches high above the forest floor. Plantlets called pups sprout from the lower side of the cluster, resulting in a huge mass of ferns that can weigh hundreds of pounds.
• The structure of the plant allows it to collect plant and animal debris in the center, not unlike a wastebasket. The debris decomposes providing vital nutrients for the fern.

• Oaxaca, Mexico
• This and all other sages are related to mints, thyme, rosemary, basil, oregano, savory and marjoram.
• This plant is a psychedelic. The herbs are eaten or, more recently, smoked. Shamans used this herb to find lost objects, hence the name.

• New Caledonia
• The Araliaceae, closely related to Apiaceae and Pittosporaceae, also contains the culinary plants parsley, cilantro, fennel, carrots, celery, anise, dill, and cumin. Also ivy, ginseng, aralia, shefflera and more.
• The genus contains about 25 species of small to medium evergreen trees.
• Each plant in this genus is dioecious, meaning a plant has either male or female flowers.

• Mexico and Central America
• Gunnera produce some of the largest leaves in the world, up to 7 feet across.
• These huge leaves are adapted to shedding large amounts of water quickly via the channels on their surface and the hanging leaf tips.

• Hawaii
• There are 900 species of tree ferns, all members of an ancient group of plants that predates the dinosaurs.
• The trunk can reach up to 25 feet tall and 10" in diameter.
• Hawaiians cooked the carbohydrate--rich starch from the core of the trunk and ate it in times of famine; it took three days to prepare. The Hawaiians have a saying: If the häpu'u is food, it is the food of death.
• They also collected the silky brown material, they call pulu, from the unfolding fiddleheads. This was used in an embalming process to replace removed internal organs. The pulu, made of thousands of brown scales, absorbed body fluids and chemicals, turning the skin to a parchment like material.
• The new fronds were also used as surgical dressing.

• Central Africa
• This brightly colored flower actually got its name from a canabalistic tribe.
• The flowers are multi-colored red-yellow-and-lime blooms shaped like a hood with a curved spur. They are just beneath contrasting, shiny foliage in the deepest shade of green.
• All impatiens plants release their seeds in an explosive burst when a ripe seedpod is touched, hence their genus name which means "impatient."
• In Africa, the leaves are a traditional dish cooked and served with plantain.

• Mexico
• These big umbrella-shaped leaves shed water from the leaf and gently direct it towards the plant's roots. The tiny hairs on the leaves also help to evaporate water from the leaf surface. In tropical environments, plants need to shed water to avoid the growth of molds, moss, algae and lichens on their leaves.

• Southeast Asia
• The Ericaceae also contains blueberries, cranberries, and our native manzanitas and madrones.
• Vireya species number over 300, approximately one third of all rhododendrons.
• In their natural environment, vireyas can be found growing as epiphytes in the moss-encrusted lofts of tree branches, on rocks, or just growing as terrestrials on the ground. They grow on the edges of forests and in open grasslands, seeking light.
• They are often the first plants to colonize areas where the original vegetation has been destroyed.

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