Somebody else might have a more definitive answer but I try to have all my pruning completed by George Washington's birthday (an easy date to remember considering his supposed chopping down of a cherry tree with his little axe). Much later and I think you might get excessive sap ooze espeically for larger limbs.

You certainly should contact someone in the University Extension network (County level, at the land grant college/university level in West Va, but additionally consider those same networks in PA and VA because of proximity) to obtain their recommendations. If I were you I would ask the time frames for both pruning and scion collection -- it would be interesting to determine if there is any difference considering both are "pruning". Getting the apple/orchard publications of these networks would be useful so that you have reference materials on hand in a file is also something that might be useful.

See also [url:lng37i6a]http://www.americanpomological.org/links.html[/url:lng37i6a].

Note there is the USDA research site in Geneva NY which is listed as a link in the above site. They might have specific information appropriate for your locale.

After consulting directly and indirectly with more knowledgeable people apparently I am right in saying that Pears and apples are more cold hardy than stone fruits but it is a mistake to imply that one is most careful by only pruning on days where it goes above freezing.
Translation in very simple terms: I personally think our West Virginia friend can certainly think about pruning now.

A question I raise for our Portland friends on a different matter: Will the cold snap we had with plunging temperatures right before Thanksgiving contribute to any winter damage for any of our fruit trees? I doubt it, but sometimes quick cold snaps before trees have hardened off are of damage.