The Elusive Butternut

Feb 6, 2023

Many people don’t realize but we have an endangered species here in Ontario. It may be right in your backyard and you don’t even know! Eastern butternut Juglans cinerea is commonly mistaken as black walnut Juglans nigra, which are widespread across the province. Butternut have been on the endangered species list since 2008. These beautiful trees have been under attack for many years now, and unfortunately succumbing to the fungal disease butternut canker. There are some butternuts that live long lives even when infected by the canker and it is believed they may have some sort of immunity. That is why it is our job to help identify as many as possible in the urban environment. Thankfully here at Royal City Tree Care we have our very own Certified Butternut Assessor, Jonathan. It is a passion of ours to help save as many of these trees as we can and potentially collect seeds from any that appear to show resistance to the canker.

Black walnut or Butternut, what’s the difference?

Both trees are very very similar and to the untrained eye almost impossible to tell apart. Here are a few key traits to get you started. Black walnut has round fruit, while butternut will have long pointed fruit. The bark on a butternut will appear smooth and black walnut bark is rougher with deeper furrows (the recesses in the bark). The leaves are also significantly different if you look closely the black walnut will have approx. 15 – 19 thin leaflets while the butternut will have approx. 11- 17 chubbier leaflets. I know that’s not really helpful! Walnut leaves will typically not have a leaflet at the end while butternut will have a leaflet at the end. To make things even more confusing their are also hybrids between black walnut and butternut. Now you see why so many confuse the two?

Our goal is to preserve and protect these beautiful trees, but we need your help! If you think you might have an Eastern butternut on your property you can contact us. We are always on the hunt for this elusive species and get super excited when we find them. You just might have this treasure hidden in your back yard!