Now, my tree-climbing days long behind me, I often think about the lasting value of those early, deliciously idle days. I have come to appreciate the long view afforded by those treetops. The woods were my Ritalin. Nature calmed me, focused me, and yet excited my senses.

The dugout in the weeds or leaves beneath a backyard willow, the rivulet of a seasonal creek, even the ditch between the front yard and the road-all of these places are entire universes to a young child.

The physical exercise and emotional stretching that children enjoy in unorganized play is more varied and less time-bound than is found in organized sports. Playtime—especially unstructured, imaginative, exploratory play—is increasingly recognized as an essential component of wholesome child development.

If a child never sees the stars, never has meaningful encounters with other species, never experiences the richness of nature, what happens to that child?

I do not trust technology. I mean, I don't think we're in any danger of kids, you know, doing without video games in the future, but I am saying that their lives are largely out of balance.

When you're sitting in front of a screen, you're not using all of your senses at the same time. Nowhere than in nature do kids use their senses in such a stimulated way.

Nature is beautiful, but not always pretty.