It's Getting Chilly at Night. Does My Horse Need a Sheet?

You walk out to the barn in the morning and there's suddenly a little chill in the air. Your horse is standing happily in the field, but you're wearing a sweatshirt for the first time in months.

And then it starts......  Should I put a sheet on my horses tonight? 

Welcome to fall, when horse owners everywhere begin checking the overnight forecast and debating whether 48 degrees is cold enough to warrant a trip to the blanket rack.

Before you start digging through the blanket bin, here's the most important thing to remember: your horse probably doesn't think 48 degrees feels nearly as cold as you do.

Horses Are Pretty Good at Keeping Themselves Warm

A healthy horse with a natural coat has a remarkably effective built-in heating system.

As the days get shorter, horses begin growing their winter coats. Those longer hairs can stand up and trap a layer of warm air close to the body, creating natural insulation. That's why you may notice your horse looking particularly fluffy on a cold morning.

So that first crisp September night doesn't automatically mean your horse needs another layer.

In fact, a healthy, unclipped horse in good body condition with access to shelter may be perfectly comfortable at temperatures that send us looking for a jacket.

The question isn't simply "How cold is it?"

A better question is:

"What conditions will my horse actually be dealing with tonight?"

48 Degrees Isn't Always 48 Degrees

Let's Imagine two nights.

The first is 48 degrees, dry and calm. Your unclipped horse has a developing fall coat, plenty of hay and access to a run-in shed.

The second is also 48 degrees, but it's raining sideways with a steady wind and your horse is standing in an exposed field.

Same number on the thermometer. Very different night for the horse. Wind and moisture matter because a horse's natural coat works best when it stays dry and can fluff up. When the coat becomes soaked or flattened, it loses some of its ability to trap warm air.

That's why cold, wet and windy deserves more attention than temperature alone.

So…Does a Turnout Sheet Help?

Yes, sometimes.

A waterproof turnout sheet can be very useful when the goal is protection from rain and wind without adding significant insulation.

But keep in mind a no-fill sheet isn't really a "light blanket."

It doesn't provide the same insulation as a filled blanket. And when you put a sheet over a horse, you're also flattening some of that natural fluffy coat that helps trap warm air.  That means putting a no-fill sheet on an unclipped horse simply because the temperature dipped isn't automatically making that horse warmer.

Think of a turnout sheet primarily as weather protection, not as a lightweight winter coat. If it's a cool, dry night and your healthy, fuzzy horse has shelter, leaving him naked may make perfect sense.

If it's a miserable combination of cool temperatures, wind and rain, a waterproof turnout sheet may be much more useful.

A Turnout Sheet and a Stable Sheet Aren't the Same Thing

A turnout sheet is designed for outdoor use and should be waterproof or highly water-resistant. It's made to protect the horse from the weather.

A stable sheet is generally intended for indoor use. It can help keep a horse clean and may be useful in the barn or during travel, but it isn't designed to keep a horse dry during a rainy night in the field.

Putting a non-waterproof sheet on a horse outside in the rain can actually make matters worse. Once the fabric becomes wet, you've got a wet layer sitting against the horse while also flattening the coat underneath.

If you're turning a sheeted or blanketed horse outside, make sure you're using something designed for turnout.

And if you've owned that turnout for several seasons, don't assume it's still waterproof just because it was when you bought it. Waterproofing can deteriorate with age, wear and repeated washing. NOTE:  Washing your turnouts with detergent or soap strips the waterproofing.  Make sure to use a product specifically designed for waterproof fabrics.  If yours has seen a few seasons, stop by Equine Exchange Tack Shop and we can help you figure out whether it needs re-waterproofing or a replacement.

The first cold rainstorm of the season is not the ideal time to discover that.

Some Horses Need Help Earlier Than Others

This is where blanket charts can get people confused. Two horses standing next to each other may need completely different things.

A clipped horse - Once you remove part or all of a horse's natural coat, you've also removed some of his natural insulation. A clipped horse generally needs blanketing sooner and requires more active management as temperatures change.

A senior horse - Older horses may have more difficulty maintaining body condition or regulating body temperature. Pay attention to the individual rather than assuming the old fuzzy pony is fine because he's fuzzy.

A thin horse or hard keeper - Body fat provides insulation and energy reserves. A horse going into fall thinner than you'd like deserves extra consideration as temperatures drop.

A horse that hasn't acclimated to the weather - A horse that recently arrived from a much warmer climate may not have the same coat or cold-weather adaptation as the horse that has lived through Pennsylvania winters his entire life.

A horse without adequate shelter - A healthy horse with a good coat standing in a dry run-in shed is in a very different situation from one exposed to wind and driving rain.

That's why there isn't one temperature where every horse in the barn should suddenly get dressed.

Be Careful About Starting Too Soon

This is where we horse owners sometimes create extra work for ourselves.

We feel that first chilly evening, put the sheet or blanket on, and then forget that tomorrow afternoon is supposed to be 72. Fall temperature swings can be huge.

Once you're blanketing, you need to pay attention to what's happening during the entire time the horse will be wearing it, not just the temperature when you're standing at the barn.  A horse that becomes too warm underneath a sheet or blanket can sweat. Now you've got moisture trapped underneath exactly when you're trying to keep the horse comfortable.

So don't just check the overnight low, look at tomorrow's high, too.

Don't Guess. Put Your Hand Under There.

One of the easiest ways to learn what works for your particular horse is simply to check him.  Slide your hand underneath the blanket around the shoulder, chest and behind the withers.  You're looking for a horse that feels comfortably warm and dry, not hot, damp or sweaty.

While you're there, take the blanket completely off regularly and look at the horse underneath it.

Check for:

• Rubs around the shoulders and withers
• Damp or sweaty hair
• Skin problems
• A blanket that's shifting or twisting
• Broken or dangerously loose straps
• Changes in body condition that are easy to miss underneath both a blanket and a winter coat

Blanketing shouldn't be a "put it on in October and see you in March" arrangement.

What About Those Horse Blanketing Temperature Charts?

They're useful, as a starting point.  They're not rules.

You'll see charts telling you exactly which blanket weight to use at 50, 40, 30 or 20 degrees. The problem is that the thermometer doesn't tell you whether your horse is clipped, thin, 28 years old, standing in freezing rain, tucked into a sheltered barn or sporting enough winter hair to resemble a yak.

We'll get much deeper into blanket weights later in this series.

For now, use temperature as one piece of information, not the entire decision.

Before You Reach for the Sheet Tonight

Ask yourself a few questions.

• Is my horse clipped or unclipped?
• Is he at a healthy weight?
• Will he stay dry?
• Is it going to be windy?
• Does he have shelter?
• What will the temperature do tomorrow after I leave the barn?

And most importantly: how does this particular horse handle cooler weather?

If you've got a healthy, acclimated, unclipped horse with a good coat, adequate forage and shelter on a cool, dry fall night, you may not need to do anything at all.

If you've got a clipped horse, an older or thin horse, limited shelter, or cold rain and wind coming through, the answer may be very different.

The trick isn't finding the magic temperature.  It's learning to look at the horse, the weather and the situation together.

And yes, sometimes the correct answer really is to leave the blanket in the tack room, even when you're standing there wearing a sweatshirt.

Coming Next: The Horse Blanket Guide

Turnout sheet, stable sheet, lightweight, medium weight, heavyweight…what's actually the difference?

Next in our Fall Blanket Series, we'll break down the different types of horse blankets and sheets, what they're designed to do, and when each one belongs on your horse.