Ex situ conservation of American chestnut (Castanea dentata (Marsh.) Borkh.) and butternut (Juglans cinerea L.), a review

Abstract

Two tree species native to North America, American chestnut (Castanea dentata (Marsh.) Borkh.) and butternut (Juglans cinerea L.), which have experienced rapid declines in their populations due to similar stressors (disease and changes in land use), are used as examples of how these species would benefit from ex situ conservation efforts. Current and past ex situ and in situ conservation efforts for these species are discussed and the focus of this review is on two key research areas: 1) what needs to be preserved (genetic information) and 2) how to preserve these trees or germplasm. Key words: butternut, American chestnut, Cryphonectria parasitica, Sirococcus clavigignenti-juglandacearum, ex situ conservation