tim,
 
I think there's a turn at line 7 with "Oh, I have picked up magic in her
nearness/To sheathe me half in half the things that sheathe her."
Before this he (speaker) seems to deny the goodness about her, she cloaks,
covers, suffocates. but after this he compares her to spring, trees; he
seems to progress from thinking 'she binds me' to 'she binds me, but she
heals me; her binding (sheathing) protects me.'
 
theres no clear subject to 'hath' but I would suppose it relates to 'her,'
since she seems to be the object of comparison to trees.
 
tina