Over 15 years ago I planted a collection of grafted chestnut trees and chestnut seedlings. During the next few winters I lost all of my grafted trees to winter damage but all my seedlings survived the cold temperatures. Before I lost my Bouche de Bétizac I was able to do a controlled cross with a pure American Chestnut. Bouche de Bétizac is a French cultivar that was developed in 1962 and is the controlled cross between Castanea sativa and Castanea crenata (female Bouche Rouge × male Castanea crenata CA04). It is a productive tree that produces a very large nut that is said to have a good flavor. I grew the American tree from seed sent to me from the American Chestnut Cooperators 30 years ago and it has had no winter damage with -30F temperatures. This tree has never shown signs of blight as others of my chestnuts have. The seedling that I have grown from this cross is now 14 years old and growing nicely in the warmer and more acidic soils of the Berkshires of Western Massachusetts. Next to this cross I’m growing a collection of other Chestnuts including 15/16th American Chestnuts from the American Chestnut Foundation as well as a relatively newly Bouche de Bétizac. I also have planted Bouche de Betizac seedlings, a pure European seedling, Silverleaf and Marki seedlings. In the surrounding forests are pure Americans that after time all succumb to the blight.
I’m excited about my cross since it has the chance of inheriting blight resistance from both parents, hardiness from the American, gall wasp resistance for Bouche de Bétizac and quality of the nut. I don’t know what qualities my cross is going to have but I would love to share scions with anybody that is interested in grafting it. I believe that graft compatibility might take best grafted onto Bétizac seedlings.
Have you heard of the cultivar called Silverleaf (also known as Eurobella)? I got my seedling from Burnt Ridge Nursery and I’m really pleased with how well it has done. Here is a photo of the chestnut, most likely crossed with my pure American but not sure.
After reading your post, I just changed my order to a layered clone of Belle Epine (late ripener) and added seedlings as backup of my other 2 grafted orders. Layered clones are essentially large cuttings without a graft union. I’m told the University of Minnesota master gardener program warns of delayed graft failure in Zone 4 for nut trees.
I found these available at Burnt Ridge as layered clones labelled zone 4, sorted by approximate ripening order: Colossal (early, pollen sterile), Okei (mid), Maraval (mid-late, zone 5), Belle Epine (late), Nevada (late).
I love your approach of testing flavor and planting chestnuts your climate, it’s really great. I’m glad that you mentioned the layering of chestnuts. I have a Maraval that is layered which is still alive in Vermont but really not that happy with our sweeter soil. What I have found is that my chestnuts take a number of years before they start shooting up. I have a complex hybrid that is timber form and is growing up to 5 feet a year and has just started to produce nuts in the past 2. When I was a little kid my grandfather told me of the forests of Massachusetts before the blight, must have been maravalous.
It surprises me that a tree at the maturity level to produce chestnuts succumbed to frost. Burnt Ridge Nursery lists the Bouche de Betizac as suitable to zone 4. I have bought this one amongst numerous other grafted varieties. Do you use protective measures in the wintertime to protect from damage? I heard painting the trunk with the white latex paint is good for preventing sunscald.
If I’m remembering correctly we went to -25F the winter that Bouche de Betizac died back so severely. I had it planted in a location where the low winter sun was blocked by forest to the south of the tree. My Massachusetts tree is in its 5th winter and doing very well.
