We were hiking lately in Canadian Rockies (the Kananaskis country) and kept encountering branches of conifers near ground covered in brown substance similar to mud or excreta.

small conifer with its tip covered in a brown substance

It didn't have any strong smell but it also was mostly dry and looked quite old. There were many occurrences mostly, but not only, along trails.

One of the hiking books we have here calls this a "rarely seen bear toilet paper".

page of a book with and image of the substance

However, for us this definitely wasn't "rarely seen" and I also doubt it to be bear's poo as there was just so much of it everywhere. What is this? And if it's a bear's poo why do bears do this?

EDIT: After asking on Facebook some people suggested it's a kind of fungal infection. Though they weren't able point out the species. What kind of fungi may this be?


1 Answer 1


In your photograph, it looks like the crown of a small conifer. Unless a bear reached up to swing the top down to assist in the force applied to its behind, it's unlikely that a bear's poop would be on the top of a tree. So, not bear poop.

The saying is, "Trees grow from the top up and die from the top down." That deterioration is called crown decline or crown dieback and happens to branches sometimes as well. Seeing this in multiple trees, not rarely, and near the trail, indicates that these trees are experiencing significant stress. That it's happening along hiking trails may be because there is compacting of soil or some other human activity affecting the tree's roots, and therefore its vigor.

When we were in the planning stages of building our house on wooded land, the builder warned us that heavy equipment compacting the soil would kill trees as far as 15 feet away or more from the tree (it was a fairly mature forest.) He wisely told us to pick the trees most important to us in planning our driveway and building site. These trees were marked, and tape was put up along the route of the future driveway and the house. It saved us from the nasty surprise many homebuilders face a few years after their home is finished. God bless conscientious builders!

  • $\begingroup$ Thanks for your thoughts. I'm still seeking an exact answer to what that substance is. It's definitely not the tree "just dying" as there is this brown thing on top of the branches. After asking on facebook some people suggested it's some kind of fungal infection. Though they weren't able point out the species. $\endgroup$
    – Jen
    Aug 13, 2022 at 20:22
  • $\begingroup$ Also, although the photo depicts a crown of the three the three was still small enough for a bear to reach up there with his bum. .) $\endgroup$
    – Jen
    Aug 13, 2022 at 20:25
  • 1
    $\begingroup$ @Jen - You'd need a lab analysis to determine the exact nature of the substance. Most likely it's composed of multiple communities of microorganisms present on dead organic matter. When the organic matter no longer nourishes these communities, the whole thing tends to dry up like dry gangrene. So you won't get a definitive answer here. :) $\endgroup$ Aug 15, 2022 at 11:45

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