Scratch-and-Sniff Trees

A few trees have a distinct smell that can help you identify them. Out west, if you dig your nose into the bark furrows of a Ponderosa pine, you might a whiff of butterscotch. Here in Wisconsin, scratch at the bark of a black cherry and the odor of bitter almonds may make you cough. My favorite local tree with an unexpected smell, though, is the yellow birch (Betula alleghaniensis). Peel back its bark, sniff, and what you’ll smell is the fresh, minty scent of wintergreen. This is one foolproof way of distinguishing it from its cousins the paper birch and hophornbeam, which we also have here.

Oil of wintergreen is an organic compound produced by a number of plants, probably to deter herbivores. This is the stuff that makes wintergreen lifesavers spark, thanks to triboluminescence. (If you have no idea what I’m talking about, go into a dark room and look in a mirror while chewing up a wintergreen lifesaver with your mouth open. You’re welcome.)

Other plants also produce oil of wintergreen as well – we have its namesake plant, wintergreen, here, which is a small forest floor plant with red berries and shiny dark green leaves, and there’s another birch species elsewhere on the continent, sweet birch, that smells even more strongly than yellow birch.

What plants can you identify by smell?

7 replies on “Scratch-and-Sniff Trees”

I was just talking about thiswit ha co-worker today while in the field! I passed on to her that I was taught that the leaves of Sambucus canadensis (Elderberry) smell like corn nuts and the leaves of Solanum dulcemara (Bittersweet Nightshade) smell like peanut butter. Two others that readily spring to mind that I have learned (that even I, with a remarkably poor sense of smell, can detect)are the leaves of Scutellaria lateriflora (Mad-dog Scullcap) which smell like mushrooms, and the leaves of Asimina triloba (Paw-paw), which I don’t think you have in Wisconsin, that smell like diesel fuel and green peppers!
I have always been very envious of those lucky folks who use their sense of smell almost as much as I do my sense of touch when identifying plants!

I have a poor sense of smell, but there’s a few that I do notice. Wild leeks, of which there are plenty in the woodlands here in S. Ontario. Also, when I’m mowing the trail out back here, there are a few places where I encounter mint, which always delights. Then there’s stinkhorn (phew!) – they suddenly appeared last year out of the mulch on the flower beds – not so nice!

Mockernut Hickory leaves are fragrant when crushed. They don’t smell like anything in particular, just sort of generically spicy. Sweet Gale and Spicebush also come to mind.

Comments = love!

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s