Christine Orfeo, age,10, of Lancaster, Pennsylvania, for her question:
Where is the eucalyptus tree found?
Before we tackle today's topic, let's introduce ourselves to the word "indigenous." In ordinary language, you are born with certain indigenous features and you yourself are indigenous to your homeland. Science uses the term "indigenous" to mean native born. The eucalyptus tree is indigenous to faraway Australia and Tasmania.
Nowadays, the eucalyptus appears in many movies and TV shows. It plays a bit part in westerns because it happens to be part of the natural scenery. But the stately tree with the shaggy bark and long, dripping leaves is not indigenous to America. By that we mean that it is not a native tree descended from a long line of American ancestors. Today we can find perhaps 100 different eucalyptus cousins thriving contentedly in the New World. But 200 years ago there was not a single one. The splendid group of trees and shrubs was discovered by the glamorous explorer, Captain James Cook. He found them in the 1770's, when he and his team of naturalists explored and charted the warm moist slopes along the coast of Australia. The eucalyptus also is indigenous to Tasmania.
The great tree still thrives in its native home, along with 525 of its smaller cousins. All of them axe fast growing, hardwood evergreens. They are thirsty because a lot of moisture evaporates from their papery foliage. The giant blue gum eucalyptus grows taller than 300 feet. Its long, silvery green leaves rustle in the breeze and every month it sheds a few of its leafy ribbons. Ragged patches of bark peel from its pale trunk, but the big tree is never bare.
Eucalyptus trees are very useful and soon after they were discovered by Captain Cook they were growing in many new lands. In parts of Texas the big trees are planted in swamps where their thirsty roots drain the land. In Florida and California they are planted around citrus groves where they soon grow into tall, leafy windbreaks. Many smaller trees and shrubs are cultivated in parts and gardens. They make themselves at home in almost any moist, warm winter region. The tangy scent of eucalyptus comes from gummy resins. Shipworms and other saltwater borers detest this resin. The hardwood lumber of the big trees is valuable for building ships and piers, walls and roofs. The fine wood can be polished smooth and used to make furniture and indoor paneling. Lumber is taken from trees about 30 years old. But as it grows, a big, gum tree may be performing other useful duties. It may be helping to drain a swamp or shel¬ter an orange grove. And a useful chemical called eucalyptol can be extracted from its whispering foliage.
Eucalyptol is better known as eucalyptus oil. Its refreshing fragrance is somewhat like the scent of camphor. We smell it in nose drops and many other medications during the stuffed up, sniffy season of the year. The human body finds this tangy eucalyptus oil warm and peppy, but certain germs detest it.
The sturdy little white gum and the eye catching silver dollar gum with leaves like silvery gray coins can be grown in a 12 foot tall greenhouse, maybe even in Alaska. But no gum tree can abide a cool winter outdoors, even in Pennsylvania. Their favorite states are California and Florida, and in the moister parts of the southwest, a traveler often sees a stately row of tall blue gums growing beside an old road through the prairies.