I e-mailed my forester brother the pic's and asked about the "pecan" and "ring-porous". I don't know if it'll help anyone out, but i got the following response from him:
"ring-porous" is a term used define the arrangement of the vessels or "pores" in hardwood trees. In a ring porous species the vessels formed in the early wood and late wood are clearly two different sizes, one forms large vessels and the other small. In a diffuse porous species (most hardwoods are diffuse) the vessels formed in the early wood and late wood are all essentially the same size. As the wood changes from sapwood to heartwood a growth of cells called tyloses kind of plugs up the vessels. This occurs differently or not at all depending on the species. I believe hickory commonly has tyloses. I think this is why you will see the newer pores seem to be open while the older ones appear to be plugged. I am not really sure how this affects the quality of the wood for bow-making but I can do a little research. Also, I can't tell from the picture if yours is ring-porous or diffuse porous but I would guess that it is diffuse porous. I don't think you got a bad tree, just a representative tree for our area. Also, I verified that it is a Mockernut Hickory. I think he is correct in that most of our hickories (Water, bitternut, black, and mockernut) are "pecan hickories"