Hi Bill,

Check out "The American Barn" by Randy Leffingwell (ISBN 0-7603-0109-3) where in Chapter 9 - Barn Renaissance an explanation is provided to your query.

From 1900 onwards Sears, Roebuck and company sold thousands of mail order "Honour Built" barns which were indeed constructed from top grade yellow pine with the option of cypress for siding.

Ken Hume