North American Fruit Explorers mailing list at ibiblio

[Kevin Bradley <kbradley@ttlc.net>]

My Ures have survived unscathed for about ten years now in zone three. What 
kind of rootstock do you use? I would consider using ussuriensis and 
burying the graft union. (If you use communis this should help also)
Occassionally, maybe one out of fifty or less, they will die for no 
apparent reason after several years. I believe this is pear decline. 
Burying the graft union should alleviate this also.
Also, if your trees are already on ussuriensis and they are dying, it could 
be due to a shallow water table, ussuriensis can't stand poorly drained or 
wet soils. (although two feet has beenok in southern WI for ussuriensis but 
the drainage sensitivity may be affected by stress brought on by other 
factors.)
Kevin B
www.edibleforestnursery.com