I have a citrus (key lime) that spends winters in my crawl space under my house. I have lighting on timers and circulating fans etc and all is well generally. We had a cold snap at the end of November and I noticed (after catching the critter) a mouse had neatly chewed the bark off the lower portions. It promptly defoliated but all the stems have remained green and healthy looking above the affected areas.
My question is should I do anything to help or have I done the best that can be hoped for by bringing this into the house?

Cheers, Barrie.

My comments assume the mouse has removed the cambium all the way around the stem. If not, the tree may recover on it's own.

If the lime is on it's own roots, or the mouse chew above the graft, it is likely that it will sprout below the chew portion.

If the tree is grafted, and damaged so that it cannot resprout, or if you just want to try to save the top portion, it may also be possible to bridge graft, or use some other grafting method to repair the damage. I have made smiliar grafts and they worked fine, but they were done when the plant was in active growth. I think such a graft may work when the tree is dormant too. It is worth a shot.

Thank Ned,
So far everthing looks fine aside from the fact the cambium layer was chewed off in the lowest sections. I was initailly concerned with transpiration which did eventually lead to a complete deloliation. Stems are strong and green, a good sign. I think if anything serious was going to happen, it would have already been showing up. It's been about 3 weeks. I guess time will tell.

Cheers, Barrie.

Plant stems will often remain green when the outer bark has been removed but if there is no bridge of bark across the area that has been stripped, the part above the damaged area will eventually die, as will the part below the damage, (if no new stems sprout below the damage). If the continuity of the bark is completely removed from a woody plant, it will seldom survive. Sometimes it will live long enough to bridge the gap itself, but not as a rule.