Species At Risk


(Juglans cinerea)
Butternut occurrences map


Butternut is a medium-sized tree that can reach up to 30 m in height. It belongs to the walnut family and produces edible nuts in the fall. The bark of younger trees is grey and smooth, becoming ridged as it ages. Butternut is easily recognized by its compound leaves, which are made up of 11 to 17 leaflets (each nine to 15 centimetres long) arranged in a feather-like pattern. The fruit is a large nut that contains a single seed surrounded by a light green, sticky, fuzzy husk.


Butternut can be found throughout central and eastern North America. In Canada, Butternut occurs in Ontario, Quebec and New Brunswick. In Ontario, this species is found throughout the southwest, north to the Bruce Peninsula, and south of the Canadian Shield.


In Ontario, Butternut usually grows alone or in small groups in deciduous forests. It prefers moist, well-drained soil and is often found along streams. It is also found on well-drained gravel sites and rarely on dry rocky soil. This species does not do well in the shade, and often grows in sunny openings and near forest edges.


Butternut Canker is a fungal disease that spreads quickly and can kill a tree within a few years. This fungus has already had a devastating impact on North American Butternut populations. Surveys in eastern Ontario show that most trees are infected, and perhaps one-third have already been killed. Some infected butternut trees live for many years. Experts hope this is an indication of resistance to the disease.


Naturally occurring Butternut are protected under Ontario’s Endangered Species Act. Planted trees are not protected, unless they were required to be planted as a condition of a permit issued under the Act. Section 5 of Ontario Regulation 242/08 provides detailed information on Butternut protection under the Endangered Species Act. Contact your local Ministry of Natural Resources office to ask for details before you consider cutting a Butternut.

What You Can Do to the Butternut

  • The Ministry of Natural Resources tracks species at risk such as the Butternut. You can use a handy online form to report your sightings to the Natural Heritage Information Centre. Photographs with specific locations or mapping coordinates are always helpful. nhic.mnr.gov.on.ca
  • The Forest Gene Conservation Association is interested in learning where Butternuts are surviving the Butternut Canker disease. To report Butternut trees or for help getting trees assessed for Butternut Canker or finding seed and seedlings, contact the Ontario Woodlot Association at www.ont-woodlot-assoc.org or visit the Forest Gene Conservation Association website at www.fgca.net.
  • Private land owners have a very important role to play in Butternut recovery. If you find Butternut on your property, you may be eligible for stewardship programs that support the protection and recovery of species at risk and their habitats.
  • Contact the Ministry of Natural Resources before removing any naturally-occurring (e.g., not planted by humans) Butternut tree of any age on your property, even if it is dead or dying.
  • If you are planning to log your woodlot, a certified tree marker can help you select the trees to be removed to ensure the continued health of your forest.
  • Consider removing trees that are shading Butternuts in order to help keep them strong and encourage seed production.
  • You can learn how to identify Butternut and the Butternut Canker by visiting www.lrconline.com/Extension_Notes_English/pdf/bttrnt.pdf.
  • Report any illegal activity related to plants and wildlife to 1-877-TIPS-MNR (847-7667).
  • Volunteer with your local nature club or provincial park to participate in surveys or stewardship work focused on species at risk.

Did you know?

At first glance, Butternut can look similar to its close relative, Black Walnut. Don’t be fooled! Unlike Black Walnut nuts, Butternut nuts are oval, not round. Its leaves have a prominent end leaflet where Black Walnut’s is small or missing.

Did you know?

Aboriginal people used Butternut medicinally to treat toothaches, injuries and digestive problems.

Did you know?

There are about 13,000 Butternut in Ontario. Its scattered presence makes it difficult to do a complete inventory.

The Endangered Species Act

Contact your local ministry office

Often the best source of local information on species at risk is your nearest ministry office. Call with your questions or concerns.