Dear John The fact that you see nor taste any difference does not mean that in several genes there could be changes. Moreover any detrimental genes are, I am sure, selected against by taking the proper cuttings. By the way do you know how the original Cox Orange of 100 years ago tasted? Lastly exceptions confirm the rule, most clones of vegetatively propagated plants have to be replaced by new ones due to loss of vigour. Ben J.M.Zonneveld Institute of Biology,Leiden University, Clusius lab Wassenaarse weg 64, 2333 AL Leiden, The Netherlands Zonneveld@rulbim.Leidenuniv.NL Fax: +31-71-5274999. min temp -10C (15F)