We manufacture log homes, and we get a fungal stain that we call blue stain in our pine that looks a lot like that. It is caused by loggers who cut the trees and let them lay for too long in hot weather before getting them in and getting the bark off of them so that they can dry.
Typically, it doesnt harm the structural strength of the fiber, but it detracts from the appearance.
Had I recieved that piece of wood from Track, I'd have been on the phone with them in about a minute, and we would have been trading wood. Those guys are good up there, and they back their products. If you call them and voice your concern they will do all they can to make it right. But, ya gotta call them first, or they dont know that there is a problem. They would have no way of knowing that the guys in the warehouse had sent you a substandard chunk of wood.
Bill