apples don't root well via cuttings. they are better off grafted onto another apple. air layering can be done but has low numbers as well. If you plant 100 apple cuttings maybe 5 will root but I'd be tempted to say 0. I personally have never seen anyone root an apple or pear via cuttings but have seen them both air layered and rootstocks are often mound layered to get more rootstocks. I have seen plums rooted via cuttings with low numbers but try it out it can't hurt anything and let us know how it works out.
