As the nature deficit grows, another emerging body of scientific evidence indicates that direct exposure to nature is essential for physical and emotional health. For example, new studies suggest that exposure to nature may reduce the symptoms of Attention Deficit Hyperactivity Disorder (ADHD), and that it can improve all children's cognitive abilities and resistance to negative stresses and depression.

We cannot protect something we do not love, we cannot love what we do not know, and we cannot know what we do not see. Or hear. Or sense.

Kids are absolutely starved for positive adult contact.

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.

As a species, we are most animated when our days and nights on Earth are touched by the natural world. We can find immeasurable joy in the birth of a child, a great work of art, or falling in love.

A widening circle of researchers believes that the loss of natural habitat, or the disconnection from nature even when it is available, has enormous implications for human health and child development. They say the quality of exposure to nature affects our health at an almost cellular level.

These days, unplugged places are getting hard to find.