True, Bingle, disembodied for me is *usually associated with a more astral variety of disconnection, such as a disembodied spirit. But, still, the usage of disembodied in the sentence you described didn't really bother me, and immediately produced a clear image of a complete, severed limb. Would you have preferred:

"The severed arm lay askew against the base of the pecan tree, its bloody tendons staining the once-aromatic bark."...?

disembodied>disemboweled

Is a disemboweled body disembodied from its bowels...or vice versa?

Grisly, isn't it?