Butternut Tree

(Juglans cinerea)


  • A medium-sized tree growing to 30 m in height, belonging to the Walnut family
  • Smooth bark when young, becomes ridged with age
  • Compound leaves of 15 to 17 leaflets (each 9 to 17 cm long)
  • Produces large, edible nuts each fall that grow singly and are surrounded by a light green, sticky, fuzzy husk


Endangered Provincially and Nationally


Eastern North America from Georgia, Alabama, Mississippi and Arkansas west to Iowa and Missouri, north to southern Ontario and Quebec, east to New England. In Ontario is found throughout southwestern region north to the Bruce Peninsula and the edge of the Precambrian shield. (ROM)


Naturally this was a tree that occurred sparsely in forests and was therefore not ever very common in Ontario, however they have further declined with clearing of forests.  The main threat to Butternut most recently is a serious fungal disease called Butternut Canker, first identified in Ontario in 1991 and thought to have arrived accidentally in infected plants imported from overseas.  The canker enters the tree through cracks or wounds in bark and can kill the tree within 3 years of becoming infected.  Spores of the canker spread easily across many miles in wet weather.  Surveys in Ontario show that most trees are infected, and perhaps one-third have been killed.


  • Ontario‘s Endangered Species Act: prohibits any type of harm to this species. Butternut is protected from being cut on national and provincial park land in Ontario, but most trees occur on private land
  • Ontario Forest Gene Conservation Association: has established a Butternut Conservation Group that is working to locate disease-resistant individuals and use them to propagate tree seedlings to reestablish healthy Butternut populations in Ontario


Ministry of Natural Resources: Butternut

Royal Ontario Museum: Butternut


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