If there's a Big Bad Wolf lurking somewhere out there, Bruce Leighton invites him to come calling on his straw house.

"Everybody says, `What are you going to do when the Big Bad Wolf comes and blows the house down,' " Leighton says."If he shows up, I'm going to invite him in for a beer because I don't think he can do it."

Leighton's house has weathered high winds, heavy rains and temperatures ranging from more than 100 degrees to less than 20. And so far, the little two-bedroom cottage he built out of bales of hay is doing just fine.

Straw houses are catching on across the country, and are most popular in the Southwest, says Jon Stetson, who operates Out on Bale by Mail, a company based in Tucson that shows people how to build them. That's because the houses are inexpensive and easy to build, and they're easy to heat in the winter and cool in the summer, Stetson says.

Some people have a construction contractor do the building, although Stetson says the bigger savings come when people like the Leightons do it themselves.

Leighton, a burly man with flowing gray hair and beard, acknowledges that one reason for building a straw house was his stubbornness. Until retiring to the Ozarks a few years ago, the 58-year-old ironworker traveled the country, building bridges and tall buildings - and living in houses that other people built.

"We've lived in so many homes that were built for somebody's else's tastes, or the market, or some such foolish thing," he says. "When we decided to build a home of our own we decided we were going to do it our way."

Dixie and Bob Peterson had an entirely different reason for building a straw house in Oronogo, 90 miles to the southwest.

Dixie Peterson suffers from chemical sensitivity, and the farm chemicals sprayed in her neighborhood each year had forced her to move out for months at a time. Several years ago she learned that the chemicals found in her conventionally built home were sickening her, and she had to add on a special room.

Now they are moving permanently into their straw home and going to elaborate lengths to make sure it is free of chemicals. They couldn't spray the straw with insecticide so they constructed an elaborate system to keep bugs out, including sand barriers in the frame.

At the Leighton home, the owner is particularly proud of the contraption he built to provide heating and air conditioning. A series of pipes connects to his well and his hot-water heater and he runs hot water through them in the winter and cold water in the summer.

Leighton says he's made a point of following building codes that would apply to a large city like Springfield, 20 miles southwest. He realizes that his 50-acre farm, surrounded by forest and hills, is being encroached upon by civilization, and his neighbors probably won't always be the deer he now sees from his back porch.

Both couples estimate their homes cost about $20,000, though they both tell of hearing how some people have spent many times that on more elaborate homes.

And both couples are sure that the Big Bad Wolf won't rob them of their investment.