You often see that pink to red color in box elder wood. They call it "Flame Figured" I guess to describe the color and pattern. I can't remember for sure if it's caused by a beetle or a disease. If the wood is old and dry, the color will likely stay. If it's still a little green, it might disappear when it dries as Jess suggests. Slab it, dry it, stabilize it, and enjoy it!