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[Lucky Pittman <lucky.pittman@murraystate.edu>]

> The Sept 2004 issue of the NNGA Nutshell included an article from Dr. 
> Charles Spurgeon, the NNGA Butternut Inventory Committee Chairman.
> In it he summarized some of his experiences of 25 years with grafted 
> butternut, buartnut, and heartnut(all on eastern BW rootstock) in his 
> grove, which has a 'well-developed and well-nourished naturally-occurring 
> strain of the Sirococcus fungus'.

'Ayers', 'Bountiful', 'Coble #1', and 'Kenworthy' - all selections which 
have been propagated as 'butternut' for years - are healthy, but recent 
genetic testing has revealed these to be, in actuality, buartnuts - hybrids 
of butternut and heartnut.
Eight other named butternut clones(Bear Creek, Beckwith, Booth, Buckley, 
Chamberlin, Creighton, My Joy, VanSyckle) in his grove are all severely 
affected and in decline, while some known hybrids are mildly affected.

Dr. Spurgeon put forward the following suggestions, based on his experience:
"1. All true butternuts are at risk from the Sirococcus fungus and those 
that appear healthy are either hybrids with Japanese walnut(or the heartnut 
bud sport), or are in isolated stands that have not been exposed to the fungus.
 2. Butterjap and buarts are variably tolerant of the Sirococcus fungus; 
resistance ranges from partial to complete.
 3. Pure Japanese walnut and its bud sport heartnut are completely 
tolerant of Sirococcus, presumably because both evolved together."

Dr. Spurgeon's take-home message was:
"The BAD news  - pure butternut is a dying specie that will likely become 
extinct in the not-too-distant future.  The GOOD news is that hybrids of 
butternut with Japanese walnut and heartnut can be used to replace pure 
butternut - and, in fact, there are several of these hybrids which have 
been mistakenly identified as butternut for several decades.
The future is already here for  Sirococcus-resistant butternut hybrids."