Elizabeth Ivanyi, age 11, of Vancouver, British Columbia, Canada, for her question:

Which is the tallest member of the grass family?

The earth is adorned with hundreds of different grasses and the tallest ones grow higher than a house. Our velvety lawns are classed as turf grasses and all of the different species we use are among the dwarfs of the family. In our meadows grow various taller grazing and forage grasses. They provide food for domestic cattle and horses, plus numerous wild animals that eat vegetation. The meadow grasses also provide seeds for countless birds.

Wheat, rice and other popular cereals are grasses that grow several feet tall. Corn is a much taller member of the grass family. And sugar cane is a grass that grows from seven to 15 feet tall. However, all these grassy herbs are midgets compared with the giants of the family. These are the sturdy bamboos that thrive in moist, warm regions of the world. Their skinny leaves grow from joints in their stiff woody stems. The tallest bamboo grass may stand 100 feet high and the base of its smooth, tough stem may be 12 inches thick.