One of the most intriguing interpretive tours I’ve joined across the national park system was the “wild cave tour” offered at Mammoth Cave National Park. For six or more hours in sections of the cave off-limits to the more traditional tours we scooted through tight places on our bellies when not able to get by on hands and knees.

Imagine taking the time to go into your backyard, or the nearby woods, or even a pond close to your home, to catalog all the life you found in it. Not just the deer or snakes or fish, but the birds and insects, reptiles, plants and fungi and everything else biological or botanic. Imagine how fascinating that would be. At Great Smoky Mountains National Park they've been working on just that, and what they've found has been incredible.

Though much of the news involving national parks and marijuana plantations has been focused on Sequoia National Park, a bust the other day in Yosemite shows that that park has some pretty fertile ground for pot as well.

How much would you pay to hike a trail in Shenandoah, or Great Smoky Mountains or Sequoia? What do you think is a reasonable fee to take a dip at Cape Cod or Cape Hatteras national seashores?