The 1x10 base trim on my exterior battered columns have shrunk, warped and twisted such that the mitered joints have broken and reveal large gaps. These base trims were replaced in a remodel which occured approx. 9 years ago. I would like to replace them. What do you recommend as a suitable material (type of wood) and method (type of joint) and caulking / sealing procedure to assure that they hold their shape. I have seen some original similar trim pieces on other homes which have survived the test of time.