Pork Butt Defined
Despite the name, pork butt does not come from the rear end of the hog--it is cut from the shoulder.
The pork shoulder weighs 12-18 pounds and consists of two portions: the butt, which is the upper portion of the shoulder, and the picnic, which is the lower portion.
The whole pork butt is a rectangular roast weighing 6-10 pounds and containing a portion of the shoulder blade bone. It is sold bone-in or boneless; if boneless, a whole roast may be cut into half portions.
The whole picnic weighs 6-9 pounds. It contains a portion of the foreleg and is usually sold with some skin attached. The picnic is sometimes cut into an upper arm portion (the meatier portion, usually sold skinless) and the lower foreleg portion (containing more bone, skin, and connective tissue).
Post #7 in this thread has a picture of the cutshttp://www.smokingmeatforums.com/for...ad.php?t=80581