Make sure it's well watered 24 hours before you move it. Put masking tape around what's left of it....a couple of wraps to keep the stems erect. Dig it up, divide, plant in mud, keeping the crown above the wet soup, keep it shaded (burlap works good for this) and it should love you for rescuing it from the deer. Oh, and don't keep watering it...wait until the soil starts to dry out.

(If the weather is extremely hot, dry, windy, its a good thing to mist the burlap a few times a day to keep a cooler, more humid 'microsphere' around the plant while it settles in. And make the move in the late evening.)

I used to live in NW Oklahoma where the summers are brutal and I never hesitated to transplant anything (although I did not have hosta) at any time, using the method above.

Alternatively, you could pot it up and place it under some shrubs...I have some yews in front of my house that I use for a plant emergency room.

back in the days of yore.. the olden days.. when the idiot was young and virile ... lol ...

that is how they sent crown divisions in the regular old mail ... just celery stalks .... there is less stress on the plant to sustain the leaf ... and the petioles are green .. so they process sunlight ...

believe it or not.. i am not even sure you need the tape.. because w/o the leaf.. whats there to pull them down .. and who cares if they flop ...

life will all be in the new flush ...

frankly i dont know if i would do it a few weeks before the hottest time of the year .. but again.. you have no large leaf surface to be harmed..

just do it ...

ken

BTW.. if you need a smaller hosta.. just go get a smaller hosta.. and quit bonsai 'ing this one ... why do you keep dividing it.. find a place for it.. and leave it alone .. or what.. you just like the excersize???? ... its not vigorous.. because you keep torturing it.. whats that all about?????