Protecting untreated pine
I recently had an arbor built at one end of my deck. The support posts are treated 4x4 s that are set in cement below grade. The posts and cross beams are then wrapped with untreated pine. I plan on painting the arbor but I'm looking for suggestions to best protect the untreated pine. Should I caulk the seams before I paint to prevent water seeping to the core? The arbor is already built, so it is too late to treat all sides of the untreated boards.