Marie De Maioribus, age 12, of Huntsville, Alabama, for her question:

How does a tumbleweed live?

When we notice a tumbleweed, it is a big ball of brown dead twigs, bowling down the road or over a field. Naturally you wonder how in the world such a plant manages to survive. Actually, what we saw was merely the last stages of its existence. It sprouted last spring from a seed and all summer it thrived among an assortment of other wayside weeds. By summer's end it was a round green bush, perhaps two feet tall. Its multitude of twigs were ready to produce a multitude of small seeds.

When the seeds were ripe, the tumbleweed's greenery withered away. Its dry stem broke off at ground level and the first passing breeze gave it a shove. The big ball of dry twigs tumbled on and on, blown by the wind. And as it went, it dropped its seeds. The tumbling tumbleweed is a parent plant sowing its seeds for a new crop of tumbleweeds next year.