Q. Your book is subtitled Saving Our Children from Nature-Deficit Disorder. What is that?

A. It’s not a medical diagnosis, but a way of getting a handle on an issue by naming it. I define it as the price all of us pay, especially children in their developing years, for alienation from nature. We pay a price in terms of cognitive development; the full use of our senses; being able to pay attention to the world around us; and our physical and mental health.

Q. Nature has proven therapeutic benefits.

A. A study at the University of Illinois suggests that direct physical contact with nature reduces symptoms of ADHD for kids as young as 5. It may also help with depression, obesity, and stress reduction.

Q. Can nature help kids learn?

A. In the late ’90s, a series of studies was done on schools that emphasized outdoor classes. Not only were grades higher, but so were standardized test scores. Scandinavian studies also show that kids play more creatively and cooperatively on natural playgrounds with grass and trees, versus flat, boring, conventional playgrounds.

Q. Are computers the problem?

A. I’m not against computers, but there’s little evidence they’re good learning tools. When you’re using a computer, you’re not using all your senses—only playing in nature stimulates them all. To me, the most important word is wonder. It’s hard for a kid to feel a sense of wonder in front of a “Grand Theft Auto” video game. But if he gets out in nature, it’s guaranteed he’ll eventually feel wonder.

Q. Does playing a sport help?

A. The greatest increase in childhood obesity happened during the same two decades as the greatest increase in organized sports. One night of soccer a week doesn’t make up for the loss of exercise from just playing outside.

Q. Why don’t kids play outside as much these days?

A. I originally thought reduced access would be the main issue, but I discovered the most important issue for parents was fear. We’re terrified of stranger abductions, when statistically it doesn’t add up. The unrelenting, 24/7 media coverage of a few tragedies is scaring us beyond reason.

Q. Are there other obstacles?

A. What I call the “criminalization” of natural play—a combination of laws, well-meaning environmental restrictions, and neighborhood covenants. My own community association has torn down all the tree houses and forts in our canyons.

Q. How can we help turn the tide?

A. We can intentionally take our kids into the woods. Take them fishing. Leave part of our yards unmanicured. Encourage schools not to cut outdoor education programs but to expand them. Scout programs should focus more on nature; girls can’t climb trees at Girl Scout camps now for fear of litigation. City planners should look at Western Europe’s “green urbanism” movement, which brings nature into people’s lives rather than divorcing them from it. Kids shouldn’t have to go to Yosemite to see something wild.

Q. What about nature education in schools?

A. Educator David Sobel talks about ecophobia. When kids only learn about things like the disappearance of the rain forest and the ozone layer, they forever will associate nature with Armageddon and tragedy. They need to learn natural history in a balanced way.

Q. What’s your greatest goal?

A. I hope to help shift natural play from a nice but “frivolous” activity to one of the things you should do if you’re a good parent, grandparent, or teacher. All the great things nature does for kids, it also does for the adults who take them there: better attention, better health, stress reduction. Nobody loses in this; everybody gains.