Butternut Archive Update: Spring 2026 

On June 4, Upper Thames River Conservation Authority (UTRCA) staff retrieved and planted 40 grafts from 14 different parent Butternut trees from across Ontario, as part of our partnership with the Forest Gene Conservation Association (FGCA) and their efforts to conserve and restore Butternut throughout Ontario.  

Butternut is listed as Endangered both federally and provincially as a result of the Butternut Canker (Ophiognomonia clavigignenti- juglandacearum), a fungal pathogen. Butternut Canker has been found in 99.7% of the Ontario population of Butternut trees and causes significant decline in their health, leading to mortality. 

These grafts represent genetics from putatively tolerant trees to the Butternut Canker. The FGCA has established six Butternut Archives across Ontario. The UTRCA maintains one of these archives located on one of our properties near Innerkip. On site we currently have 158 parent trees represented by over 460 grafts planted. This spring, we have observed female flowers, male flowers, and seed developing. We are hopeful that this potential crop develops into mature seed that can be collected and grown on to support the recovery of this species.  

For more information visit the FGCA's website: Butternut Resources – FGCA.