I have Yellow Pine flooring which has shrunk since install 2 years ago. Is there a way to fill the cracks? I was thinking something like a tile grout that would fill the cracks and allow me to refinish and stain? Some of these cracks are almost 1/2 an inch! The flooring has also cupped. I did get the crawl space encapsulated and had to put some foundation jacks in to level after the fact. I really need some help here!