4 min read


Why Do Dogs Smell Trees



4 min read


Why Do Dogs Smell Trees




It has been said that dogs experience the world with their nose the same way humans experience the world with their eyes. Dogs don’t have the best vision, but their ability to detect, identify, and differentiate smells more than makes up for it. The area of a dog’s brain devoted to analyzing different smells is more than 40 times the size of the corresponding part of the human brain. Dogs have 220 million olfactory receptors in their noses, compared to 5 million for people. A dog’s nose is as sensitive and capable of sensing detail as human eyes. So it’s no wonder that a dog relies on her nose as much as her owner relies on her eyes.

The Root of the Behavior

Your dog has a large cluster of olfactory nerves in your nose, called the “Jacobson’s Organ.” The correct name is the vomeronasal organ. It’s found in other animals, such as cats, cows, horses, and all snakes and lizards. By inhaling the air near a place where another animal has made a scent marking (by doing such things as releasing urine or feces), the animal can detect the pheromones and find information about the animal that left the marking. This is the reason snakes will stick their tongues out – they are trying to detect prey. Another example of the use of this organ is a motion called “the flehmen response.” The animal will lift his head while wrinkling his nose and lifting his upper lip. He will stop breathing momentarily in order to process the pheromones. 

Dogs like to urinate on landmarks like trees and signposts in order to show that they have been there. It’s a little like bathroom graffiti: “Joe was here!”, “So was Tim!”, “And Bob was also here!” By sniffing at a tree, for instance, a dog can tell a lot about who was there, like their species, their gender, their general health and even their emotional state. To a dog, sniffing a tree is like reading Reddit; all the information you could ever want to know, and maybe some you are afraid to ask. It’s a way for a dog to get some social interaction. She has the same craving for information that you do. 

Of course, dogs don’t limit themselves to peeing on vertical landmarks, and they don’t limit themselves to only sniffing things like trees and fireplugs. For instance, dogs have scent organs in their paws. After your dog eliminates, you may see her rubbing her feet on the grass in a gesture that almost looks like she’s washing her hands. What she’s actually doing is leaving a scent marker with pheromones.

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Encouraging the Behavior

There really isn’t anything you need to do to encourage your dog to sniff trees, or anything else. Snuffling and sniffing is her way of getting information. The best thing you can do is to give your dog space to sniff around and examine her surroundings. Often, however, we treat walking our dogs like a chore. We fit it in before work, after work, after dinner. We have very busy lives, and all too often, our puppies get the short end of the stick. Taking the dog out for a short walk may allow her to eliminate and gives her a chance for light exercise, but it limits her exposure to the larger world, and it deprives her of the chance to fully experience her environment. Plus, it limits your bonding time.

Give your dog as much time as you can. If you can only take her out for brief walks most days, make time to take her to the dog park or on a very nice walk where she will have plenty of time to sniff around to her heart’s content. Alternately, find a dog walking service, like Wag, that can give your dog the exercise and mental stimulation she needs.

Other Solutions and Considerations

While it’s important that your dog gets the chance to interact with her world through her nose, you need to make sure that she is safe. Keep your dog on a leash unless she is in a secure environment. Be sure to keep an eye on what she is sniffing. Your dog has a different definition of gross than you, but there are still hazards to her out there, even if they smell interesting. Make sure she is not eating the poop she finds, and be sure she is not pawing at any dead animals. Watch out that your dog doesn’t inhale any irritants, either naturally occurring or artificial. Keep an eye on your dog and if her nose is running after a long romp, consult your vet’s office, as she may have inhaled something bad or dangerous.


You and your dog may be together, but in many ways, you live in different worlds. Beyond the obvious fact that you drive a car and go to work, your dog sees, or rather, smells, a completely different world than you simply by using her nose. Give her the chance to experience it.

By a Chow Chow lover Jodi Mai

Published: 03/16/2018, edited: 01/30/2020

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