Flora

by Christopher Baker

Home : Travel : Costa Rica : CR Handbook : One Article


Costa Rica has an extraordinary abundance of flora, including some 9,000-plus species of "higher plants." There are many more species of ferns in Costa Rica--about 800--than in the whole of North America, including Mexico. Of heliconias, members of the banana family more familiarly known as "birds of paradise," there are some 30 species. It is a nation of green upon green upon green.

The forests and grasslands flare with color, some flamboyantly so, for plants like to advertise the delights and rewards they have to offer, including the ultimate bribe--nectar. Begonias, anthuriums, and blood of Christ, named for the red splotches on the underside of its leaves, are common. My favorite plant is the "hot lips" (labios ardientes), sometimes called "hooker's lips" (labios de puta), whose bright red bracts remind me of Mick Jagger's famous pout or--more appropriately--Madonna's smile. The vermilion poró tree (the bright flame-of-the-forest), pink-and-white meadow oak, purple jacaranda, and the almost fluorescent yellow corteza amarilla are trees that all add their seasonal bouquets to the landscape. And morning glory spread their thick lavender carpets across lowland pastures, joined by carnal red passion flowers, unromantically foul-smelling--a crafty device to enlist the help of flies in pollination.

Many plants play out the game of love and reproduction in the heat of the tropical night, when they emit their irresistible fragrances designed to attract specific insect species. Other flowering species employ markings on their petals to indicate the exact placing of the rewards insects seek. Many orchid species, for example, are marked with lines and spots like an airfield, to show the insect where to land and in which direction to taxi (see "Orchids," below). Others display colors invisible to the human eye, yet clearly perceptible by insects whose eyesight spans the ultraviolet spectrum.

The most abundant flora in rainforest environments are ferns, light-gap pioneers found from sea level to the highest elevations. The ancient terrestrial ferns once served as food for many a prehistoric beast. The big tree ferns--sometimes called rabo de mico ("monkey-tail") ferns, an allusion to the uncurling young fronds--are relics from the age of the dinosaurs, sometimes a dozen feet tall, with fiddleheads large enough to grace a cello. Others are epiphytic, arboreal "nesters," or climbers whose long leaves can grapple upward for 60 feet or more.

The epiphytic environment (epiphyte comes from the Greek, "upon plants") is extremely poor in mineral nutrients, a kind of nutrient desert. The bromeliads, brilliantly flowering, spiky-leafed "air" plants up to four feet across, have developed tanks or cisterns which hold great quantities of rainwater and decaying detritus in the whorled bases of their tightly overlapping stiff leaves. The plants gain nourishment from dissolved nutrients in the cisterns. Known as "tank epiphytes," they provide trysting places and homes for tiny aquatic animals high above the ground. Costa Rica has over 2,000 species of bromeliads (including the pineapple), the richest deposit of such flora on the isthmus.

All plants depend on light to power the chemical process by which they synthesize their body substances from simple elements. Height is therefore of the utmost importance. When an old tree falls, the strong, unaccustomed light triggers seeds that have lain dormant, and banana palms and ginger plants, heliconias and cecropias--all plants that live in the sunshine on riverbanks or in forest clearings--burst into life and put out big broad leaves to soak up the sun, to flower and to fruit. Another prominent plant is the poor man's umbrella (sombrilla de pobre), whose name you'll remember if you get caught in a downpour while in the rainforest; its giant leaves make excellent impromptu umbrellas.


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