The jar was round upon the ground (7)
Terrific. Even though this jar commands the wilderness, it's so boring we can hardly stand it.
It did not give of bird or bush (11)
Ah-ha! So the wilderness has something the jar doesn't have after all. Things in the wilderness can breed and grow of their own control. You could trap a baby bird in a jar (but don't, guys, that's cruel), but you certainly couldn't create one with a jar.