Mary Gonzales, age 9, of Beaumont, Texas, for her question:
HOW TALL DOES BAMBOO GROW?
Bamboo is a giant grass. There are about 500 to 1,000 different kinds of bamboos and most of them grow naturally in tropical climates or in the warm regions of temperate climates. Some types grow to be 120 feet tall and have stems one foot in diameter.
Scientists rank bamboos among the most primitive of grasses. They are distantly related to wheat, oats and barley.
Two kinds of bamboos are native to the United States. They form the well known canebrakes found in the southeastern states.
Bamboo provides many essential articles for people who live in tropical countries, especially Asian lands. A farmer may live in a bamboo house, sit on bamboo chairs and eat food prepared in bamboo containers. His bed and cover may be bamboo mats. He wears sandals woven from bamboo strips.
In addition, the farmer keeps his chickens and pigs in bamboo cages and encloses his yard with bamboo fences. He also eats the tender young bamboo sprouts as vegetables.
Bamboo is also used to make rafts, sails, tow rope, paper, ornamental screens, cooking untensils, tools, baskets and building materials. There is probably no other substance in tropical countries that has as many uses as bamboo.
Bamboos have been grown in the United States mostly for ornament.
Bamboo usually grows from new shoots that sprout from the base of the mature plant. The shoots grow quickly. one bamboo grew 36 inches in 24 hours.
Not all of the bamboos grow fast, but most of them reach their full height within a few months. Old clumps that have stored much food produce the largest and tallest bamboos.
The jointed stem never gets thicker after a bamboo is full grown. Bamboo stems do not add a ring of growth each year as tree trunks do.
Bamboo leaves grow alternately in two rows on opposite sides of the stem. They are long and narrow, but have short stalks, unlike the leaves of other grasses. When the leaves mature, the blades usually fall off, leaving the sheath like base.
Bamboos rarely bloom. Some have blossoms only once ever 30 years. Then all the bamboos in the area may bloom at the same time. Only the branches near the top of the main stem bear blooms. The plants usually die after they bloom.
The United States Department of Agriculture maintains a bamboo garden near Savannah, Ga. Here, experts grow bamboo and test it. They have found that the closely matted roots help control soil erosion and the high cellulose content of bamboo stems makes excellent pulp for paper.
Construction engineers also use bamboo. Experts who compared the strength of laminated or layered bamboo with soft steel found that its breaking point nearly equaled the breaking point of the steel. The strong, lightweight bamboo makes an excellent reinforcement for concrete.