smsmith,
Yes Golden Spice is Pyrus x ussuriensis as are most cold hardy pears http://trees.umn.edu/nursery-tour/species/gosppe/. Similarly Ure is grafted to harbin http://www.burntridgenursery.com/URE-EUROPEAN-PEAR-Pyrus-communis/productinfo/NSEPURE/. You might be interested in these scions available from ARS GRIN http://www.ars-grin.gov/cgi-bin/npgsold/swish/accboth?query=ussuriensis&si=0&start=75. You might also want to look at this nursery Pears – St. Lawrence Nurseries as they will have zone 3 pears. There are many more zone 3 pears than what there once was. Not sure if your on the Canadian or U.S. side but Canada has the new Russian cultivars. You might be interested in this post Krazulya Pear - #2 by clarkinks
3 Likes