Читать книгу Handy Pocket Guide to Tropical Plants - Elisabeth Chan - Страница 7

Screwpine

Pandanus spp.

Botanical family: Pandanaceae

Pandanus tectorius (see left and far right) is a very common sight along Old World tropical beaches. Formerly known as P. odoratissimus, it is a medium tree-like plant. It has a trunk and very obvious prop roots and its leaves are gathered in a large, stiff clump at the top. Often there is a fruit looking somewhat like a pineapple. It is a multiple fruit, an attractive orange or red when ripe, made up of clearly defined carpels which when fully ripe, break off, and—if not eaten by an animal—can be seen lying on the beach waiting for the tide to take them to another spot to germinate. P. tectorius is often planted in seaside gardens because of its ability to withstand strong, salty, sea winds.

The leaves are long, dark green and very stiff, with spines along the edges and, in some species, along the midrib. They are spirally arranged on the trunk, hence the common name. These leaves are of economic importance in village and cottage industries, where the work is done mainly by women. Initially the leaves are cut and the spines stripped off (a painful procedure). Then the leaves are torn into various widths, dried and tied in hanks, dyed with synthetic dyes, and woven into mats, baskets, hats, trays and other objects for sale in tourist markets.

Pandanus amaryllifolius (opposite middle left), is a domesticated species without spines of which many forms have been cultivated, including one called the Pandan serani the 'Eurasian pandan' in the Malay language. The origin of this name is obscure. P amaryllifolius is a small species of about 50 cm characterized by very sweet-smelling leaves. It is cultivated extensively throughout India, Sri Lanka and Southeast Asia to provide flavoring for food. It is also grated very finely into a pot-pourri mixture for temple and altar offerings and, rather peculiarly, to be placed in drawers and taxis to deter cockroaches.

The species on opposite top left is P. spiralis which has a marked twist to its habit of growth, and the variegated form, opposite bottom, is a cultivated ornamental.

Tree Fern

Cyathea spp.

Botanical family: Cyatheaceae

Tree ferns are forest dwellers, partial to dim coolness and damp. Some are found in lowland forests where they do not grow very tall (up to 3 m). The tree ferns found in the hills and upland areas of the tropics do very much better and are a conspicuous feature of these areas. They also grow in more open secondary forest.

The tree fern resembles a delicate palm tree. It has a rough and hairy trunk, marked with the remains of leaf bases. The fern fronds at the growing tip look like palm fronds as they are concentrated at the top of the trunk.

Within the genus they are easy to pick out, but to identify species requires a deeper knowledge of the scaly young parts and leaves. A clue may come from the name, taken from the Greek word for cup, kyatheion: this is what to look for in the cover of the spore cases that are found on the lower side of the fern frond.

Tree ferns are often logged for the horticultural trade as the trunks make good growing poles for epiphytic plants.

Bird's Nest Fern

Asplenium nidus

Botanical family: Asplemaceae

This is a popular house plant in temperate climate homes where it forms a dainty roseate of about 10 cm. In its native Old World tropics it can grow to 2 m across.

In its natural habitat, Asplenium nidus varies in size depending on its location and the availability of water and a continuous supply of decomposing detritus from trees and insects which provide the fern with nutrients. This matter falls into the 'nest' formed by the fronds which grow in alternately overlapping circles.

A colonizing fern, it is epiphytic on suitable trees, but is commonly seen on the ground where it has fallen from its perch but continues to grow As the fern grows upward and outward simultaneously, the root mass becomes deeper and spongier and is able to hold a great quantity of water. This attracts other fern spores to colonize the root mass. In some Malay rural areas, the plant is believed to have supernatural properties, or of being the home of the lansuir, a female banshee hostile to pregnant women.

Gingers

Alpinia purpurata; Costus speciosus; Nicolaia elatior, Tapeinochilus ananassae; Zingiber officinale

Botanical familys: Costaceae; Zingiberaceae

Gingers are among the flashier members of the plant world. They have a high profile in coffee-table books and are the mainstay of the tropical cut flower industry.

Costus speciosus (see opposite centre left) is a member of the family Costaceae. The fleshy velvety leaves grow spirally around the stem in a characteristic clockwise direction. The stem is cane-like, reddish and tall, and the dark red inflorescence is terminal on the stem. The white or slightly pink flower, tubular with a pretty frill, emerges from the bracts and is edible. The rhizome is used for medicinal purposes.

Tapeinochilus ananassae, also from the family Costaceae, is appropriately known as the wax ginger (see far right). The plant produces canes that are dark red in color and tall, but, unlike the Costus speciosus, it branches at the top of the stem. The inflorescence has large bracts—red, shiny, stiff and pineapple-like—with insignificant flowers. It does not grow tall; several cluster around the base of the plant.

Alpinia purpurata (on bottom right) is a zingiber. It is a popular landscape ginger, the pink form of which is called 'Eileen Mcdonald'. The plant propagates itself by producing plantlets from the flowering bracts.

Nicolaia elatior (on opposite top left) belongs to the Zingeberaceae. Called the torch ginger, its leafstalks are tall, about 10 to 15 m and the 'torch' itself is about 1 to 2 m. Torches, produced singly from the ground on a long stalk, are composed of big flower heads of waxy overlapping bracts with small flowers. In Southeast Asia they are visited by small sunbirds, as each row of flowers opens in turn. The bud is used sparingly as a flavoring for food.

Zingiber officinale, the oldest 'Oriental' spice known to the Western world is the familiar ginger rhizome used worldwide (see above left). Although it was recorded in China 500 years ago, its place of origin is unknown, but it is suspected to be an Indian cultigen.

Banana Plant

Musa spp.

Botanical family: Musaceae

Any discussion of tropical plants must include the banana. Yet ethnobotanists do not know exactly where the fruit originated. The most generally accepted theory is that as the Indo-Malesian area is the main center of diversity, this is strong evidence of origin.

There are hundreds of edible banana varieties; in Indonesia alone there are over 230 recorded, but the bananas of commerce are far fewer, due to considerations of quality, aesthetic appeal, flavor and so on. The two species banana that are considered to be the parents of most of the edible seedless bananas eaten by man are Musa acuminata and Musa balbisiana.

The banana is such a pan-tropical that it grows everywhere man has planted it. It is even said that the slaves in the West Indies for whom the breadfruit was painfully collected by Captain Bligh, declined to eat it because they preferred bananas.

Species bananas are more interesting botanically, even though they are tasteless or full of seeds. Pictured here are three of the more spectacular varieties. The banana with the incredibly long fruiting stem is called the 1000 banana plant in Indonesia and Malaysia. Even if the actual number of bananas does not reach 1000, the bunch is a marvel of nature: It is sometimes so long and the fruits so numerous that the bunch reaches the ground.

The banana pictured on the top left is Musa velutina. The pretty red fruits actually peel themselves from the base of the fruit up, to entice a potential customer to eat them and thereby spread the seeds. The banana (opposite middle left) with the striking red flowers, Musa coccinea, is purely ornamental as its fruits are small and hard.

In addition to being eaten fresh, bananas may be cooked, chipped, made into alcoholic drinks or processed into starch. The leaves are used to wrap foods or to line utensils in which food is prepared. The flowers of the inflorescence and the center of the stem are also edible.

Cordyline

Cordyline terminalis

Botanical family: Dracaenaceae

Cultivated for their beautiful leaves, cordylines are native to Australasia, the Pacific Islands and tropical America. The center for cordyline development is Hawaii where it is known as the ti plant. In Asia, collectors look to Thailand.

Most cultivated cordylines have long leaves that vary in width and length. They grow in a roseate form at the top of a stem that is marked all the way up the stem by the scars of the leaf sheaths. Some newer hybrids have leaves twisted like corkscrews, and many other cultivars have broad leaves or leaves that are almost cup-shaped. In all cordylines, the flowers are inconspicuous. The leaves come in all colors except blue, black, pure yellow, pink or other delicate colors. There are many variations on the rose-purple color, and there is a striped green and white form.

The landscaping style created by Roberto Burle Marx, now popular in public landscaping all over the tropics, has made the cordyline an essential element. Planted in blocks of a single color, they are striking and easy to maintain.

Codiaeum

Codiaeum variegatum

Botanical family: Euphorbiaceae

Codiaeum are found in almost all tropical gardens, parks, roadside plantings, Botanic Gardens and cemeteries. They are popularly and inaccurately called 'crotons'. They are almost trouble free and are very colorful ornamentals. The flowers are inconspicuous, but the shiny leaves come in innumerable variations or color, shape, size and rorm. The forms commonly seen are cultivated varieties of plainer, duller, single color species now rarely seen. As they are so variable, the only way to ensure that a plant is the desired one is to propagate it vegetatively.

Codiaeum are indigenous to Malesia and the Pacific. They come in all colors except blue, black, pink and purple. There are many named varieties, and recently, Thai horticulturalists have developed dwarf varieties suitable for the pot plant culture of urban areas. Codiaeum are useful as specimen plants, hedges and as part of a general planting. The taller specimens reach about 2 m and they require full sunlight. They can give a garden a 'hot' tropical look.

Aroids

Alocasia macrorrhizos; Amorphophallus paeoniifolius;Caladium x. hortulanum; Monstera deliciosa; Pistia stratiotes

Botanical family: Araceae

Araceae are a large botanical family classified at present into 2,500 species. The plants pictured here belong to a tiny part of them. They do not resemble each other in any way noticeable to a casual observer, but they illustrate the vast range of tropical aroids that exist.