Jack Abel, age 9, of Cleveland, Ohio, for his question:
How does a cactus grow in the desert?
The cactus dares to live where there is no hope of water for months at a time. It has learned to cope with life in the dry, sunny desert. There, the showers are few and far between. When they come, they often pelt down with violence, washing the sand and light soil down into gullies and hollows. Very little life‑giving water sinks into the ground to feed the roots of the desert plants.
Most plants need moisture in the soil and a little rain every few days. The cactus plant has learned to do without. In fact, a thousand or more vastly different cactus plants have learned to survive in the dry desert. There they thrive and add beauty to the arid wasteland.
Their problem is to store as much precious water as possible. Their roots do not go deep into the dry soil. The root system of even a tall cactus spreads out wide, just beneath the surface. That way every drop of water is soaked up before it runs away.
Another problem is to prevent the drying air from evaporating moisture from the plant surfaces. On a summer's day gallons of water will evaporate from the leaves of, say, an oak tree. Cactus plants to not have the luxury of delicate leaves. That seem to be cactus leaves are really swollen stems. They bulge with stored water and are covered with thick skin to prevent evaporation.
Each cactus is a water reservoir. In the desert, water is riches. Every little bird and animal would steal it from the cactus if he could. So the cactus has to defend itself from robbery. The green, fleshy parts of the plant are smothered with prickles like pins and needles. Protected against robbery, sun and drought, the sturdy cactus has the desert almost to itself.
The world's most handsome cactus plants grow in the southwestern deserts of Arizona and New Mexico. They are grey‑green, adorned with a smattering of bright fruit. In the spring, they burst into a riot of color. Your gift encyclopedia has a colored page of beautiful cactus blooms.
The giant saguaros stand like tall sentinels across the valleys and over the hills of the desert. They stand like huge candlesticks, sometimes 50 feet high, pointing their grooved trunks and branches at the sky. The saguaro bears a posy of blossoms like white dinner plates with golden centers.
Most common of the cactus plants is the prickly pear, a short, stubby fellow with stems like small ping pond paddles. Its huge, delicate blooms range from pale yellow to vibrant orange. The flowers fade and are replaced with juicy purple fruit. Another favorite is the ocotillo, a graceful bunch of tall, slender stems. The ocotilla adds flame red tassel blossoms to the desert garden.
The barrel cactus looks just like a fat green barrel. For a short time it wears a wreathe of yellow blossoms on its head. The hedgehog cactus has more prickles than most. It is a, dumpy plant with pink or deep red blossoms. All these and many more outwit the arid desert and, for a short spell, burst forth in gorgeously colored flowers.