What you need to know about black walnut colic in horses and why shavings matter.

Title: When Shavings Turn Sour: Black Walnut Colic in Horses

Picture this: you’re cleaning stalls after a long day, the stable smells like hay and peppermint soap, and your horse nuzzles a bale of bedding with curious gusto. It’s a normal moment in a rider’s life—small, everyday routines that keep a horse happy and healthy. But every now and then one simple choice can cause big trouble. In this case, the culprit isn’t a stubborn stomach alone—it’s the very shavings some barns rely on for cushioning and comfort. Specifically, black walnut shavings.

What is black walnut colic, anyway?

Let me explain the heart of the matter. Black walnut colic is a type of severe abdominal distress that can occur after a horse ingests shavings from black walnut trees. The wood contains substances that can irritate or affect the gut, and in some horses this can lead to a dangerous, painful episode. When that happens, you’ll see signs that scream “this hurts now”—and fast.

It’s helpful to separate it from other colics you might hear about. Gas colic, for instance, comes from gas building up in the intestines. It can be uncomfortable, but the pattern isn’t driven by wood shavings. Impaction colic is a blockage somewhere along the GI tract where feed, sand, or other material has tightened into a knot that’s hard to move. Equine gastric ulcer syndrome isn’t a blocking problem in the intestines at all—it’s ulcers in the stomach lining that can cause dull grief and appetite changes. Black walnut colic, by contrast, is its own story: a specific trigger from the wood that can provoke a sudden, painful bout of abdominal distress.

Why does black walnut cause trouble?

The exact biology can be nuanced, and not every horse reacts the same way. What we know for sure is that many vets and horse owners report a strong connection between black walnut shavings and colic-like symptoms. The chemicals in the wood appear to irritate the gut and make the horse react with restlessness, sweating, and a racing heartbeat. It’s not a mystery you want to solve in the field—these signs can escalate quickly, and time matters.

A quick tour of the signs

What should you watch for if your horse has been around black walnut shavings? The list isn’t glamorous, but it’s essential:

• Sudden, severe abdominal pain. The horse may roll, paw the ground, or try to lie down and get up repeatedly.

• Sweating and an elevated heart rate that won’t settle with a simple cool-down.

• Restlessness, irritability, or a look that says “I’m not comfortable.”

• Changes in behavior, such as reluctance to move, looking at the flank, or little interest in food.

• In some cases, belly gurgles go quiet or become unusually loud.

If you see these signs, think about the environment. Was the horse recently exposed to black walnut shavings? Is the bedding situation safe and non-toxic? These questions matter because time can be the difference between a quick, minor upset and a veterinary emergency.

How this compares to other colics

Let’s keep this practical with a few quick contrasts, because you’ll hear these terms tossed around in barns, clinics, and at the barn table:

• Gas colic: Often a gut gas buildup. The pain can be intense, but it’s typically more about discomfort and less about a specific toxin.

• Impaction colic: A physical blockage. It may feel like a stubborn, persistent ache that won’t shift with movement or hay alone.

• Equine gastric ulcer syndrome: Painful ulcers in the stomach lining, usually causing subtle signs like poor appetite or irritability, not a sudden, sharp abdominal crisis.

• Black walnut colic: A distinct trigger tied to black walnut shavings. The signs can look like other colics, but the source is the wood products, not just gut inattention.

What to do if you suspect it

If you ever suspect black walnut colic, here’s a simple, practical plan:

• Stop exposure immediately. Remove the horse from any area with black walnut shavings and switch to a safe bedding option if you can.

• Contact your veterinarian. Colic can take a bad turn quickly, and a vet’s assessment is essential.

• Monitor and document. Note when the signs started, how the horse responds to gentle walking, and any changes in appetite or hydration.

• Keep the horse calm and comfortable as you await veterinary guidance. Sometimes light movement helps, sometimes rest is better—follow the vet’s instructions.

• Don’t give medicines or laxatives unless a vet tells you to. Home treatment can hide symptoms or delay proper care.

Prevention isn’t glamorous, but it pays off

The best way to keep a horse out of trouble is to prevent exposure in the first place. Here are practical steps that many barns adopt with good results:

• Choose bedding wisely. If you’re building or rethinking a stall setup, consider safe bedding options. Straw, clean wood shavings from non-black walnut sources, or other approved materials can be good choices. If you’re unsure about a wood source, ask the supplier or label the product clearly.

• Store shavings away from horses. Even if you’re not using black walnut shavings, make sure all wood products are stored where horses can’t easily reach them. It’s not just about taste—it’s about the risk of sniffing, nibbling, or wandering into a pile.

• Inspect the environment. Regularly check for any plant materials or wood products that could be mistaken for horse bedding. A little vigilance goes a long way.

• Share the knowledge. If you’re part of a team or a riding group, a quick chat about safe bedding can save a lot of worry later. It’s one of those small talks that pays off with calmer nights and healthier horses.

Real-world tangents you’ll appreciate

If you’ve ever walked through a stable aisle and noticed a mix of bedding choices, you’re not alone. The bedding world can feel like a black-and-white movie in a color-rich barn. Folks choose shavings for softness and dust control; they opt for straw for warmth; some prefer pellets for easy cleanup. The important thread tying these choices together is safety—especially when it comes to the animal you care for every day.

I’ve talked with riders who’ve learned this the hard way. A horse with even a tiny relapse of colic after a bad night can throw a whole schedule off. That’s why many barns keep a simple, practical rulebook: know what your horse is nibbling on, limit exposure to anything questionable, and trust your vet as your partner in care. It’s not glamorous, but it’s reliable—and horses reward reliability with trust and smooth rides.

The learning edge for caretakers

Knowledge doesn’t just sit on a shelf. It translates into calmer barns, healthier horses, and fewer emergency runs to the clinic. Understanding the particular risk of black walnut shavings arms you with a quick diagnostic instinct: if a horse shows colic-like symptoms after contact with a black walnut product, you’ll treat the situation with speed and care. This isn’t about fear; it’s about informed vigilance.

A few quick takeaways, so you can act fast

• Black walnut shavings can trigger a form of colic in some horses. That makes them a high-risk bedding choice in certain barns.

• Distinguishing black walnut colic from gas colic, impaction, or ulcers helps you communicate with your vet and respond correctly.

• If symptoms appear, remove access to the suspect bedding, call the vet, and monitor closely. Do not rely on guesswork.

• Prevention is practical: choose safe bedding, store materials out of reach, and keep a simple awareness in the barn about what horses are ingesting.

A closing note from the barn rail

Colic is every horse owner’s fear and every trainer’s stubborn reality—it’s sneaky, and it often shows up when you least expect it. But with clear knowledge, you can cut down on risk and keep your horse happier and safer. Black walnut colic is one of those topics that sounds almost academic until you see it in action. Then it’s all too real.

If you’re part of a riding team or a stable community, take a moment to check your bedding choices and share a quick tip with a friend. Small steps, big protection. And if you ever find your horse in distress, reach out to your veterinarian without delay. The right move at the right moment can mean the difference between a scare and a smooth recovery.

In the end, the goal isn’t to worry forever. It’s to ride with confidence, knowing you’ve done the homework—and your horse feels the difference. After all, a quiet stall and a content horse aren’t just comforting; they pave the way for good riding, steady training, and that sense of partnership that makes every ride feel like you’re exactly where you belong.