My dog suffered from Black Walnut toxicity. Learn how to protect your
Did you know that black walnut trees can harm or even kill your canine
Hans Braxmeier via Pixabay
A Little Backstory
For those of you who do not know, Thor is my Black English Labrador Retriever.
Jeannie, my girlfriend, brought him home from a professional breeder. She
actually did this without my knowledge because I was still hurting over the
loss of Dakota Sunrise, a yellow lab she had taken in who had been badly
abused and mistreated.
We have a huge backyard for the dogs to play in. We also have a tan-colored
Cairn Terrier. Because we live in a court, our larger yard is bordered by
five, count ’em, five other yards. One individual (isn’t there always one) has
seemingly never taken care of her trees. In one corner of her yard is a very
tall and strong black walnut tree.
What Is a Black Walnut Tree?
If you’re not sure what sort of tree this is, it produces green fruits that
contain the walnut. They actually look very much like crab apples, but they
are very solid and can be deadly if they hit you from a great height. In fact,
on two occasions, I have heard them fall and take a window out of another
That same neighbor had to call a tree company on another occasion because this
woman’s foliage was leaning over their house and was beginning to topple.
Thor playing in his yard
My Dog’s Experience With Black Walnuts
My difficulties with the Black Walnut began when Thor was just six months old.
He found one of those green fruits and tore the husk off of it. At the time, I
had no idea what sort of tree it was and what sort of danger it presented to
our animals. As a bit of a tree hugger, I am reluctant to cut down any healthy
tree if it isn’t totally needed.
After recognizing Thor’s proclivity towards playing with the black walnuts, I
made every effort to remove them from my yard. Toward the end of summer, they
begin to drop and it becomes a nonstop rain of destruction! I was still
working at the time, so I couldn’t be as on top of the situation as I would
Then Thor got very sick. His eyes glazed over and drool was hanging from
either side of his mouth and he froze in his footsteps. Suddenly every step
was a struggle. I had no idea it was the black walnuts. I recognized that look
though. I have seen it in the eyes of those who have partaken of dangerous
substances like LSD. I knew then it was something he had eaten.
After the first two to three hours, Thor began to drink large amounts of
water. He seemed better initially, but then he ran into our bedroom. He made a
beeline for me. I am not sure why, but he felt that it would be ok to throw up
as long as it was near me. Maybe he knew there was little he could do that
would make me overreact. I never blame an animal or a child for their actions.
you simply deal with the moment and move on.
After several more vomiting episodes, Thor had done what labs are known for.
They realize they ate something bad and they drink a large volume of water in
order to make themselves sick. In the past, we had rarely ever had an animal
so young. Jeannie has ever been incapable of turning away a stray. These
lessons were never learned by either of us although we have had many pets. I
won’t mention how many she has had in her life. As a farmer’s daughter, she
literally had barns full of homeless strays.
We learned what we should have already known, and that was keep your dog away
from black walnuts! Also, we learned that he could have died! It is literally
a poisonous plant which will spell the end of even other plant life that grows
too close to it!
I thought I had it all figured out. I was wrong. A huge branch from that tree
had been hanging over our yard depositing its ugly, poison fruit all over our
yard. I did not want another episode, so I had been very diligent in removing
them. Thor had learned his lesson, though. He no longer bothered with them
except to occasionally toss one in the air. I thought Thor had it all figured
I was wrong again. I had promised myself and Jeannie that I would cut that
branch down. The problem was it was very high up and I would have to go near
the top to cut it. Not afraid of heights, I endeavored to do this, but with a
chainsaw stalling and sputtering out in one hand, it became a frustrating
effort, to say the least. I turned then to the bow saw and cut it down the old
fashioned way. The tough tree limb was the size of a small tree. It left
branches and twigs scattered everywhere.
Black Walnuts Are Dangerous
We learned what we should have already known, and that was keep your dog away
from black walnuts! Also, we learned that [our dog] could have died!
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While I cut the log down to the size the town ordinance required, Thor helped
me order the big branches by moving them to the other side of the yard. He has
always done this. I am not sure if he is simply trying to get me to chase him
or he is actually trying to help, but he is a big help either way. Even with
the bigger logs and branches, he cannot move easily. He helps me carry by
grabbing on and following my course. It’s great laugh!
If he ever asks to get paid for this labor, I do think I will remind him how
many biscuits he eats.
After finishing up a couple hours, later all seemed well. Thor played long
into the evening and seemed fine. A few hours later, his eyes glazed over. He
stood in front of the door with twin strings of drool hanging inexorably
downward. I recognized that look. I knew instantly what happened and wanted to
punch myself right in the face!
Thor had been chewing at the sticks and twigs eagerly. He had even gone over
and licked some sap from the biggest logs. Now Thor is older. He will be two
years old in two months. He also weighs a hefty 90 lbs. He had not ingested
the fruit, but apparently the sap is enough to do the job! In fact, after
calling the vet, Jeannie learned that all tree sap is poisonous to cats and
dogs! They are drawn to it because of the sugar, not knowing the trip they are
in for. Then the vet mentioned he had lost four other dogs so far this year.
He said that since we had no real winter, the trees were giving off sap at the
After the first two hours, Thor looked better, but his strength was gone. He
couldn’t take a step. Now that he is a big fella, being sick makes it tougher
to get around. While everyone else was asleep, I could not convince him to
take another step. I got a blanket and laid it on the ground and sat down with
him for the next two hours. He was restless and jumped at every sound. I knew
he wasn’t getting any better in the chill night. I woke up Jeannie so she
could hold the doors open while I picked the big boy up. Thank god my back is
still strong, that’s all I have to say!
By morning, Thor was able to stand on his own and by evening, he was able to
run and play. He never did go through the vomiting phase this time, thank all
that’s holy. He then slept off the residual exhaustion of his long night.
Black walnut trees must not be allowed to stand in residential areas. If you
have trees that are seeping sap, one way to keep your dog away from it is to
build a taller landscape box around the trunk to close it off. Other ways are
to wrap them with chicken wire and lattice. Do what you have to do. No pet
deserves that horrible sickness or possible death.
Just another tip from Barnsey. Do with it what you will.
This article is accurate and true to the best of the author’s knowledge. It
is not meant to substitute for diagnosis, prognosis, treatment, prescription,
or formal and individualized advice from a veterinary medical professional.
Animals exhibiting signs and symptoms of distress should be seen by a
Betty on October 02, 2018:
So glad I found your article. The vet tried to tell me it wasn’t the black
walnuts, that my 3 yr old lab mix played with because they look like balls.
After a huge Vet bill they had no idea what the problem was, only that he must
have eaten something toxic. Fred had all the same symptoms you described-
lethargic, vomiting, drooling and then bloody diarrhea. My dog has a fenced in
yard and does not wander. The next door neighbor has a black walnut tree right
by our property line and all the nuts seem to fall in my yard. Fred is forever
grabbing them to play while I try to pick them up. Your article confirms what
I suspected! Thank you!
Jen on March 10, 2018:
About 2 1/2 years ago we had two large black walnut trees removed from our
property as they were close to our house and growing above our neighbor’s
garage. We found someone with a mobile mill who came to our place and milled
the logs on site.
Not knowing that these trees were toxic to dogs, the dogs stayed nearby while
we helped with the cutting and stacking of the wood. There was So much saw
dust in the air that I actually filled 13 large lawn & lead bags with it when
we finished! By the end of the day one of the dogs was unable to stand and was
very out of it. The other was also lethargic. I looked it up and found out
about the toxicity concerns. They recovered within a day or so and I didn’t
think anymore about it.
Well, within another month or so they BOTH lost their hearing. One was an 11
year old yellow lab and the other an 8 year old small Shepard/border collie
mix. Neither were all that old or were breeds that have a tendency for hearing
loss. I expect that this exposure was the cause of their loss of hearing.
Meridith on July 06, 2017:
I have an enclosed dog area that only has a black walnut tree as foliage, my
Coonhound became really sick literally overnight. Drooling, vomiting, fever
etc….he was in intensive care for four days. All of his bloodwork was good.
They did an exploratory surgery thinking he had a blockage, but found nothing.
Anyway, the Vet was at a loss since there wasn’t anything but the stomach
issues. It was winter so there were leaves and nuts around. I had moved in to
the house in the summer, so I didn’t think of the tree at all since I had been
there for so long. Anyway, I had a suspension since I have horses and know
it’s toxic to them. I should mention I have two dogs and the other has never
shown any signs. But she is very picky about what she eats and drinks. I
always keep a fresh bucket of water out and I got them a pool for the summer.
Well I was babysitting two other dogs the other day, they drank all the water
from the bucket so they started drinking or if the pool. Except one a small
dog that couldn’t reach it. Well that night all the dogs were vomiting
aggressively except the small dog. Leaves had fallen in the pool and been
there for a few days. That’s what made them sick , I would have never guessed
if the other dogs had not come over and I had not witnessed them drinking.
They recovered within 24 hours, I drained the pool and have now moved the
water bucket way away from the tree for the off chance the wind could blow
leaves into it.
Tammy Bales on February 03, 2017:
I knew the actual black walnuts were toxic but I had no idea about the
branches, sap and saw dust! We have gone through two of the scariest weeks
with our almost 15 year old chocolate lab and 3 year old black lab. Everything
started when we had our black walnut tree taken down but branches, logs, saw
dust were left in the yard! Older dog presented with shivers, GI issues and
hind end lameness. My younger dog would not stand or move on his own without
us assisting him. It happened a second time to him and he was screaming in
pain and could not stand, within 8-10 hours he was running and playing again.
These trees are toxic!
Sandy on September 20, 2016:
Thank Goodness Thor was ok. I am not 100% certain because I did not witness
our 8month old Bloodhound eat or chew any black walnuts but he has been very
lethargic, disoriented at times, drooling for a few days. He did not vomit and
his urination and bowel elimination were pretty normal. I did have him to the
vet and mentioned that he could have ingested a black walnut as we discovered
there were several laying in our back yard from a tree that is not on our
property but the branches hang over so some do land in our yard. The vet did
not seem to think our Hank ingested anything toxic. He ruled out an
obstruction via an xray and put him on antibiotics as he had a very slight
fever and also a shot of Pepcid to settle his stomach. He has shown some
improvement as he is eating and drinking much better than he was the first two
days that we noticed his symptoms. Although he does seem a little more alert
now he still appears to be a little out of sorts and lethargic. This is very
scary and we will now be very vigilant in making sure all black walnuts are
removed from our yard at this time of year before letting our Hank out. Again
we did not witness him ingesting black walnuts but he I also know that he is a
puppy and puppies chew everything and he was displaying a lot of the same
symptoms as your Thor. thanks for sharing your story. I am hoping that Hank
continues to improve and gets back to his old puppy self.
Barnsey on August 22, 2015:
Good, the tree doesn’t start to grow the walnuts until summer so you should be
able to stop it from happening next year, good luck.
Colleen on August 21, 2015:
Just found out black walnuts are toxic to dogs on Pinterest. We have a walnut
tree in our yard and a black lab who lives to chew on things. She recently
started vomiting for no reason. I now know why. We will be having the tree
removed in spring when we can afford it.
barnsey on October 15, 2014:
So sorry to hear that, Mona, Its not your fault, there is no guidebook I know
of that tells us these things and we always find out too late. Hope your dog
gets better real soon, hang in there.
Mona on October 14, 2014:
My dog is with the vet getting a barium x-ray at this point. He’s been
vomiting for months, on and off. I suspected the Black Walnut tree because
he’s interested in licking the downed nuts and husks, as well as the Water
Chestnut. After reading this, these are exactly his symptoms. He was 70 lbs.
now he’s 54 lbs. May have leaks in his intestines. So angry with myself for
not muzzling him. Bloodwork looks like it could just be the Black Walnuts, and
if I’d tested a muzzle sooner, would have known without putting him through
Bryan on October 02, 2014:
You mentioned that your vet had told you that all sap is poisonous to dogs. I
spoke with my vet, and although they couldn’t confirm this, they did refer me
to a good resource for understanding plants’ toxicity to animals, which is the
ASPCA website (http://www.aspca.org/pet-care/animal-poison-contro…
Although this site doesn’t mention black walnut as being poisonous to dogs, it
does mention many other trees and shrubs that are toxic to cats and dogs. I
see many of these plants around my neighborhood, and rarely hear of animals
eating them and poisoning themselves.
Just food for thought. I’m not a vet though so I can’t verify any of this
Sandra on September 15, 2014:
We have three 7 1/2 old black lab mix puppies, 2 boys and a girl that we
raised by bottle when their mother died while having a C-section to deliver
them. We had went thru so many trials and tribulations to keep them alive when
the chances were slim but we made it thru all of them. As they grew they were
all very strong, playful and healthy until a couple of weeks ago when our
little female started to show all of the signs of poisoning that you posted in
your story. At first we thought she must have gotten into the trash can and
ate some coffee grounds. we kept thinking it was the grounds and the vet came
out and gave her a shot for toxicity. That did not seem to work. She did not
eat for five days and only consumed large amounts of water and soon afterwords
would puke it all up. It always seemed to intensify at night and we would
sleep close to her on the floor. During the first 3 nights we thought we were
going to loose her. Her breathing and heart rate slowed down to almost
nothing. She had became so weak that she couldn’t even hold her head up. It
was such a helpless feeling knowing there was nothing that we could do to make
it all go away, except for time. Time for her to pass or time for her to
improve. After the 4th night things began to turn around for her. She slowly
started to show signs of improvement and by the 6th day she began to come out
of the stupor and weakness and gradually regained her appetite. Today is the
10th day and she is back to playful and frisky less a few pounds. but that’s
not the end of the story, about 5 days into her sickness, our male started
exhibiting the same exact signs. drull, excessive water intake and pukeing
along with confusion, and weakness. The same exact signs. So now the thought
of the coffee grounds poisioning was nixed. We for the life of us could not
figure out what was causing this thing to happen to our babies. Our 3rd lab
was not showing any signs yet and I just had to keep trying to figure out what
it was. I couldn’t handle another sick baby without knowing the exact cause. I
had to get to the bottom of this madness. I researched and researched but did
not find anything that matched the symptoms until I read your story. Thank God
for you writing about your experience with Thor. I had moved into a house 2
years ago and loved it because of all the big mature trees it had in the
neighborhood. I am not one who knows the type of trees by the shape of leaves
or type of bark, I Just loved watching the birds and squirrels do their thing.
As daylight arose, I went into the back yard to search for walnuts that may
have fallen from somewhere and sure enough was a big tree in my neighbors yard
with branches extending over on to my side of the fence and below on the
ground were several blackened moldy walnuts and husks. I had also seen
remnants tossed about the yard that had been chewed on. Once again I called
the vet to let him know the findings. He said that there is no antidote for
ingesting walnuts. I had absolutely no idea that something like this was so
toxic. You always hear about chocolate, avocados, and rasins being toxic. but
not hardly anything on black walnuts. Needless to say, the branches came down
and were removed. Being the puppies that they are, They are constantly
exploring and chewing on things. However, I am now aware of the dangers that
these black walnuts bring. Our boy is still not out of the woods yet and may
have eaten more than our female. All we can do is keep him comfortable and let
him know that we are there for him. Thanks again for your story.
Alex on March 24, 2014:
You forget to mention that Black Walnut trees are great de-wormers.
I would have loved to hear about how great the black walnut is when it comes
to take care of heart worms in our animal friends and save their lives!
Barnsey (author) from Happy Hunting Grounds on August 13, 2012:
Legally you can cut down anything that is hanging into or over your yard. Your
neighbor may like a warning that you are going to do it but you don’t even
have to give them one. I cut down a giant black walnut branch during the
beginning of the summer. Not my tree but hanging directly over my property
therefore fair game.
heinz57 on August 13, 2012:
I am so grateful to you that i came across this when i did. I have a lab that
doesn’t show any interest in my neighbors tree. Which by the way is hanying
into my yard. This article has explained one of my cats illness a week ago
though. Is there anything legally i can do to protect my pets?
Barnsey (author) from Happy Hunting Grounds on March 08, 2012:
Thank you, Thor is a little weak still but he’s going to be fine.
Tracy B from Canada on March 08, 2012:
I had no idea these tree’s were poisonous. Thank-you so much for sharing. Your
story almost had me in tears when you described his condition. 🙁 I am happy
to hear he’s alright.