The grass looks less lush. That doesn't always mean the risk is gone.
When horse owners think about grass-related laminitis, spring usually gets most of the attention.
And understandably so. Spring brings bright green pastures, rapid growth, and horses eager to get back to grazing.
Then fall arrives.
The pasture gets shorter. Growth slows. The grass may look tired, sparse, or even partially dormant. It's easy to assume the high-risk grass season has passed.
But appearances can be deceiving.
For certain horses, autumn pasture can still present a laminitis concern. Understanding why is an important part of protecting your horse's health as the seasons change.
Why Fall Grass Isn't Always Safer Grass
Grass produces carbohydrates through photosynthesis during daylight. These include sugars and other nonstructural carbohydrates (NSC), such as starches and fructans, which plants use for energy and growth.¹
Under normal growing conditions, grass uses some of those carbohydrates overnight.
But there's a seasonal catch.
When autumn nights become cold, the plant's ability to use those carbohydrates slows. According to Penn State Extension, when nighttime temperatures drop to approximately 40–45°F, the plant's overnight use of nonstructural carbohydrates can decrease significantly.¹
After bright, sunny days followed by cold nights, carbohydrate levels may remain elevated even into the morning.
In other words:
Less impressive-looking grass does not necessarily mean lower-carbohydrate grass.
Frost adds another consideration. Frost-damaged pasture can contain higher levels of nonstructural carbohydrates, adding to the concern for horses susceptible to laminitis.²
That's why judging pasture safety by how green, tall, or lush the grass looks can create a false sense of security.
Does That Mean Fall Pasture Is Dangerous for Every Horse?
No, and this distinction matters.
For a healthy horse at an appropriate body condition, pasture can be an excellent source of nutrition.
The greater concern is the individual horse's susceptibility.
Horses with insulin dysregulation, including those with Equine Metabolic Syndrome (EMS), have an increased risk of laminitis. Excess body fat or a cresty neck can be warning signs, although affected horses are not always overweight. Horses with previous laminitis require individualized management, and horses with Pituitary Pars Intermedia Dysfunction (PPID), commonly called Cushing's disease, may need closer pasture management, particularly when insulin dysregulation is also present.¹ ³ ⁴
This is where a whole-horse perspective becomes valuable.
Instead of asking only:
"Does the grass look rich?"
Consider asking:
"What's happening in the pasture, and what's happening with my horse?"
Look at the Whole Horse, Not Just the Field
Seasonal preparedness isn't about becoming afraid of pasture. It's about recognizing how several factors interact.
Taking a holistic equine-health perspective offers a useful way to approach seasonal changes: consider the horse as a whole rather than focusing on a single environmental factor.
As fall progresses, pay attention to the bigger picture.
Weather patterns: Have there been bright, sunny days followed by increasingly cold nights? Has the pasture recently experienced frost?
Body condition: Has your horse gained weight through summer? Is there noticeable fat deposition or a cresty neck that deserves a conversation with your veterinarian?
Health history: Has your horse experienced laminitis before or been diagnosed with insulin dysregulation, EMS, or PPID?
Pasture conditions: Has the grass experienced cold nights or frost? These conditions can lead to elevated nonstructural carbohydrate levels.¹ ²
Movement and hoof comfort: Is your horse moving as freely and comfortably as usual?
Nutrition and daily management: Does your horse's feeding and turnout routine still make sense for the changing season and their individual needs?
The lesson is simple:
Seasonal horse health is rarely about one isolated factor.
Grass, nutrition, metabolism, body condition, hoof health, movement, weather, and the individual horse all belong in the same conversation.
Don't Assume the Clock Tells the Whole Story
Horse owners sometimes hear that early morning is automatically the safest time to graze because grass sugars decline overnight.
That general pattern can occur under favorable growing conditions, but autumn complicates it.
When nights become sufficiently cold, plants may not use as much of the carbohydrates they produced the previous day. That means carbohydrate levels can remain elevated into the morning.¹
Instead of relying solely on a rule such as "morning turnout is safe," consider the season, recent temperatures, pasture conditions, and your horse's individual risk factors.
For horses known to be susceptible to laminitis, work with your veterinarian to develop an appropriate grazing and nutrition plan.
Know What Your Horse Is Telling You
Awareness also means recognizing when something isn't normal.
Laminitis affects the sensitive laminar structures that connect the hoof wall to the coffin bone inside the hoof. It can cause significant pain and, in severe cases, permanent structural damage.⁴
Possible warning signs include:⁴
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Reluctance to move
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A stiff, short-strided gait
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Increased warmth in the hooves
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Stronger-than-normal digital pulses
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A stance with the front feet positioned forward and weight shifted toward the hind limbs
Not every horse displays the same symptoms, and some early changes can be subtle.
If you suspect laminitis, contact your veterinarian immediately. Laminitis can be a serious veterinary emergency, and early diagnosis and treatment can improve outcomes.⁴
Want to better understand laminitis and how to recognize it? Read our companion article, Laminitis in Horses: What Owners Must Know, for more essential information on this serious hoof condition.
A Smarter Way to Think About Fall Horse Care
Spring grass gets the reputation.
Fall grass deserves attention, too.
The takeaway isn't that every horse needs to be removed from pasture as soon as temperatures drop.
It's that good horse management doesn't rely on appearances alone.
A pasture can look less lush while environmental conditions are changing what's happening inside the plant.
At the same time, your horse's body condition, metabolism, health history, hoof comfort, and daily activity all influence the bigger picture.
That's the value of approaching horse health holistically. Rather than looking at one symptom, one number, or one season in isolation, we consider how the pieces work together.
And that broader awareness can help horse owners recognize potential problems earlier.
This fall, don't just look at how much grass is in the field. Look at the weather. Look at the season. And most importantly, look at your horse.
Help Another Horse Owner Prepare for Fall
If this article changed the way you think about autumn pasture, share it with another horse owner.
A little seasonal awareness can go a long way toward protecting the horses we love.
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Frequently Asked Questions About Autumn Laminitis
Can horses get laminitis in the fall?
Yes. Horses can develop laminitis in autumn, even when pastures appear less lush than they did in spring.
Cool nights and sunny days can create conditions that allow nonstructural carbohydrates (NSC) to accumulate in grass. For horses susceptible to insulin dysregulation, consuming pasture with elevated NSC levels can increase laminitis risk.¹ ³
The key is to recognize that pasture appearance alone doesn't determine safety. Seasonal weather patterns, your horse's metabolic health, and previous laminitis history all deserve consideration.
Is grass higher in sugar after a frost?
Frost-damaged pasture can contain elevated levels of nonstructural carbohydrates, which include sugars, starches, and fructans.²
This happens because cold conditions affect normal plant growth and carbohydrate use. As a result, grass that looks dormant or less nutritious may still contain carbohydrate levels that are concerning for susceptible horses.
For horses with insulin dysregulation or a history of laminitis, frost should be a reason to reassess grazing management with your veterinarian, not an automatic indication that pasture is safe.
Is morning grazing always safer in autumn?
No. Early morning grazing isn't automatically safer during autumn, particularly after cold nights.
Under favorable growing conditions, grass uses some of its stored carbohydrates overnight. However, when nighttime temperatures fall to approximately 40–45°F, carbohydrate utilization can slow significantly. This means NSC levels may remain elevated into the morning.¹
Rather than relying on the time of day alone, consider recent weather conditions, pasture characteristics, and your horse's individual metabolic risk.
For horses prone to laminitis, a veterinarian-guided pasture management plan is the safest approach.
Which horses are most at risk of pasture-associated laminitis?
Horses with insulin dysregulation are among those at greatest risk of pasture-associated laminitis. This includes many horses diagnosed with Equine Metabolic Syndrome (EMS).³
Other horses that may require additional attention include:
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Horses with a previous history of laminitis
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Horses with excess body fat or a pronounced cresty neck
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Horses with PPID (Cushing's disease), particularly when insulin dysregulation is also present
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Horses with known metabolic abnormalities, even when they aren't overweight
Importantly, not every overweight horse has insulin dysregulation, and not every horse with insulin dysregulation is overweight.³
Understanding your horse's individual health profile is essential to making informed decisions about pasture access.
References
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Kenny, Laura. "Sugars in Spring and Fall Pastures." Penn State Extension, Pennsylvania State University. Updated September 29, 2022.
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Martinson, Krishona, and Paul Peterson. "Managing Established Horse Pastures." University of Minnesota Extension. Reviewed 2021.
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Bertin, François-René. "Equine Metabolic Syndrome." Merck Veterinary Manual. Reviewed/updated August 2025.
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Beasley, Brian. "Laminitis in Horses." Merck Veterinary Manual. Reviewed/updated June 2024.
