I have not encountered any latent graft incompatibility with
Asian pear on OHF or P.ussuriensis. Main issue with Asian pear on dwarf OHF
is runting out also unpredictable vigour.
Eric Hambly , Siloam Orchards , Uxbridge Ontario
[nafex] Graft incompatibility Asian pear,
Eric Hambly, 01/29/2013