poro and "meadow oak"

... Flora : An Overview ...
by Infocostarica Staff

Most people who haven’t been to the tropics are amazed at this region’s lush vegetation. Green in Costa Rica isn’t the green that’s found in Northern forests. The intensity of the color green is apparent even as one is flying over Costa Rica in an airplane. After being away from the country for four years, I couldn’t believe the deep color that I saw from the small window in the airplane.

Costa Rica’s flora is protected by a large system of national parks, which makes up for at least 20% of the country’s area. Thanks to these extensive protected areas, Costa Rica boasts more than 9,000 species of “higher plants”, and at least 800 species of ferns. There are many more species, some of which are widespread in the country, and some which are limited to an ecosystem or a particular area.

The tropical dry forests, which are rare and don’t contain many plants, have short, stocky trees (not more than 45 feet high). Under these canopy trees, there are smaller species of trees and shrubs with lots of prickly spines. The beauty of this strange forest is clearly illustrated during the dry season (November- March), when meadow oaks and poro trees brag by substituting their leaves with beautiful flowers of all colors. During this season, the beige color of the tree trunks and shrubs contrasts with the pastel-colored flowers, that can be white, orange, purple and pink. Dry forests are much more endangered than the tropical rain forest, because of heavy deforestation in the Northern region of the country, where they are located.

The rainforest is more popular and abundant than the dry forest; it’s being protected by several parks in diverse regions of Costa Rica. Rainforests teem with life, both flora and fauna. Since growth and decomposition are extremely rapid in this ecosystem, competition among species of flora is intense. The trees which make up the canopy or vault ceiling of the rainforest, can grow up to 100 feet tall, in order to absorb 90% of the photosynthesis that goes on in this forest. Canopy trees grow long trunks that only contain branches in its upper area. Underneath these giants, there are thousands of species of smaller trees, like the prehistoric fern-tree, as well as shrubs, vines and bromeliads. However, since the sunlight is blocked by the gigantic trees above, vegetation isn’t as thick as it could be. The key to survival in the rainforest is defined by one word: adaptation. Canopy trees adapt by reaching to the ultimate heights; vines adapt by clinging to trees and working their way up; bromeliads adapt by having “water tanks” where they hold rainwater and decaying matter which is basically their food. This incredibly diverse ecosystem has more than half of all living organisms on Earth; in Costa Rica, there are as many species of flora as in all of Europe!

There are twelve ecosystems in Costa Rica, but apart from the dry forest and tropical rainforest, it’s worth mentioning a zone that is often ignored or unknown to most people- the tidal mangrove swamps. These areas thrive with life because of this nutrient-rich environment. Costa Rica has five species of mangroves, which are defined by botanists as halophytes, or plants that can live in salty conditions. Mangroves grow in the border between the ocean and the land, and they benefit greatly from the silt and volcanic ash that rivers deposit near the ocean’s coast. These nutrients promote the production of algae and other organisms that in turn become food for larger marine organisms. Mangroves are essential for the preservation of species of flora and fauna that only thrive in these unique, salty conditions.

As you can see, flora in Costa Rica is diverse, even for such a small country. This region, which measures as much as the state of West Virginia, is responsible for the preservation of many of the world’s endangered species of flora. Furthermore, it contains species that still haven’t been discovered, and that could lead to great scientific discoveries and to medical breakthroughs. The cure for cancer, AIDS or other diseases could be growing and waiting to be discovered, in one of Costa Rica’s many ecosystems.

Costa Rica offers an extraordinary abundance of flora, including some 9,000-plus species of "higher plants". It has more species than the hole North America and Mexico. Of Heliconias known as "birs of the paradise" there are about 30 different species.

Here 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 their leaves, are common. The vermilion poro tree , pink-and-white meadow oak tree, purple jacaranda, and the cortesa amarilla are trees that all add their seasonal bouquets to the landscape.

Many plants play the game of reproduction in the heat of the tropical night, when they emit their irresistible fragrances designed to attract specific insect species. Other flowering species employ makings on their petals to indicate the exact placing of the rewards insect seek. Many orchids species, for example, are marked with marks and spots like airfields, to show the insects where to land and then where to go. Other orchids display colors invisible to the human eye, but yet clearly perceptible to the insects whose eyes cover the ultraviolet spectrum. And a remarkable holly species that changes sex to have more pollination success, being male one year and the next female. What makes them change sex is not known but it seems to be the success or lack of pollination of the year past.

The epiphytic environment is extremely poor in mineral nutrients, being a kind of nutrient desert. The bromeliads, brilliantly flowering , spiky-leafed air plants up to 1.5 meters across, have developed tanks to hold great quantities of rain water. Known ass "tank-epiphites" they provide trusting places and homes for tiny aquatic animals high above the ground. Costa Rica has more than 2,000 different species of bromeliads, the richest deposit of such in Central America.

All plants depend on light to power the chemical process by which they synthesize their body substances from simple elements. When an old tree falls, the strong, unaccustomed light triggers seeds that have lain dormant, and banana palms and ginger plants, heliconas and cecropias, burst into life and put out big broad leaves and soak up the sun, to their flowers and their fruits.