If you think of a treehouse as a tiny shack for 10-year-old boys with a “Girls Keep Out” sign scrawled on it, you’re in for a shock. The modern treehouse is a fully functional, often luxurious retreat with all the amenities one could ask for, with plumbing, electricity and all the comforts of a home.

“Tree whisperer” Pete Nelson makes these arboreal marvels possible, traveling around the country from his home in Washington state to design and build treehouses, and his work is the subject of the new series “Treehouse Masters,” premiering May 31 on Animal Planet. The nine episodes, including a treehouse tour called "Ultimate Treehouses,” range from a massive guesthouse in Waco, Texas, in the premiere to an Irish cottage in Orange County, Calif., a spa in Austin, Texas, and a writer’s retreat in Rhinebeck, N.Y.

Nelson gives us some insight into his passion for trees and how he’s turned it into a fun and lucrative career.

MNN: What’s the allure of treehouses?

Pete Nelson: They are the ultimate place into which to climb, unplug from everyday life and be with at one with nature. Or, it's a place to be with your loved ones. Or it's all of these things.

How did you start your treehouse business? How many have you built?

I started building treehouses as a business exactly 20 years ago. We have built more than 200 treehouses since then. I was building residential houses on leftover lots in Seattle and could not stop thinking about building treehouses instead. The market did not exist at the time, so it took 10 years to transition fully into building treehouses exclusively.

What got you interested in the first place? Did you have a treehouse growing up?

My dad built a treehouse for me in New Jersey when I was 5 years old or so, but I really got treehouses on the brain when I was around age 12-15. In high school I planned my first adult-scale treehouse, but it was never built. In my mid-20s, the notion of building an adult-scale treehouse came roaring back into my consciousness, and they have been there ever since.

They call you the 'tree whisperer.’ Why?

I feel that this title comes from looking closely at what the trees have to offer in the way of structure. I work with trees to create an efficient platform that will not damage the tree and will not be overly complicated to construct.

Treehouse Brewing Company in Ohio with Pete Nelson

Treehouse Brewing Company in Ohio. (Photo: Animal Planet)

What are the things you consider in building a treehouse?

Many factors go into sitting a treehouse: views, sun, proximity to power/utilities, the trees themselves and of course species, maturity and health. There are many factors to consider. It gets easy if you only have a few trees from which to choose. Build strong. Allow the trees to move and grow. Look into the specialized hardware on several treehouse websites.

How do you ensure not harming the tree?

Don't pepper the tree with fasteners. Don't girdle (strangle) the tree, and do not compact the root system under the tree.

What kind of trees are best?

There are only a few trees to avoid: cottonwoods (they drop big heavy branches out of nowhere); and short-lived trees like alders. My favorite trees are Douglas fir, Western red cedar, maples (all kinds), oaks (not swamp oaks, but almost all others, especially big live oaks).

Temple of the Blue Moon with Pete Nelson

Temple of the Blue Moon at Treehouse Point in Washington state. (Photo: Animal Planet)

Any other favorites?

I visited a treehouse in Hawaii in a Monkey Pod tree in the early '90s. It was amazing. I guess they typically grow up to 20 feet or so and then open up like the palm of a hand. They get enormous too. Otherwise, my other favorite is a baobab, the very fat stubby ones that grow on Madagascar and elsewhere in Africa.

What's your mission in doing this?

My mission is to spread excellent information on how to connect responsibly to living trees.

Are you involved in any forest conservation organizations?

We are starting Tree For All, a nonprofit to get people with disabilities into treehouses!

What’s the most unusual treehouse you’ve built? The biggest? The most unusual? Most challenging? The highest elevation?
The Irish Cottage in a Huntington Beach, Calif.: olive tree. The Maddox house in Waco is the recordholder now; the biggest burned down in the San Diego County wildfires of several years back. The Ohio treehouse brewery build was tough. It was freezing! The highest: 144' at my hotel, Treehouse Point.

What’s it like there?

Treehouse Point is a remarkable piece of property to begin with: Beautiful mature trees of big scale. It was a blank canvas, in a sense, as I have been able to experiment and build purely for the purpose of sharing the magic and power of treehouses with others. Amenities are the Raging River, the forest and nature itself. The treehouses are quite comfortable as well, and I understand that the breakfasts have an excellent reputation.

To borrow an old Barbara Walters question, if you were a tree what kind of tree would you be?

I'd be a willow along a nice trout stream. That would be nice.

This guy may be the best treehouse builder in the world (and he just got his own TV show)
Pete Nelson sees a tree and asks a simple question: Why do birds get to have all the fun?