Ever read something that makes you want to just throw the book across the room? How is it that so many writers honestly don't seem to have the imagination to realize that cold and heat might have the same adverse effects on horses and other animals that they do on humans?
Reading just now about an intrepid hunting party trotting their tireless nags through knee-deep, drifting snow triggered a strong urge to say bad words and throw things. I value my walls (if not the book) and refrained. I won't even get into the effect of such weather on the hunting and restrain myself to the image of horses trotting merrily through snow up to their knees. I have news for this author. Not even the high-stepping show ring beauties like Saddlebreds can manage this trick for more than a few strides, even in the lightest powder snow.
Let's examine how snow and ice and cold really affect the equine and the rider. Those of you not from snowy climes, be aware that the quality of snow varies, from super-dry in very cold conditions to wet, mushy masses the closer to freezing you climb. Dry snow squeaks underfoot and is wonderful for skiing and miserable for walking or riding. It clings to everything and is like wading through sand. As it warms up and settles, it gets worse. Try wading through it and I guarantee that in a few feet you will be panting, in a few yards you will be sweating, and after that you'll be wanting very much to be at your destination, however far that it is.
Horses wear out very fast in this. Four years ago we had an extremely hard winter here, with 3-4 feet of snow on the ground for months. Something spooked my two in the night (my guess is neighbor dogs). The mare plowed over a gate and Beau, my 16.3 Saddlebred, broke the wire fence and fled about 60 feet into the open. And stalled. And stayed there until I came down in the morning. He was belly-deep in it, and I sank so far I could not touch the ground and had to wade/swim out to him. He was eager to follow me home, but had a really hard time floundering through it, even following his original trail. We were both breathing pretty hard just in that 60 feet.
Note from this very old hunting picture how quickly even a few horses can trample down an area. This makes easier going for the horses in the rear, but look at the lead horse. He's in it up to his knees. The man leading it (probably my dad) will be the one breaking trail, and the hunters/horses will trade off to rest and put someone else in the lead.
Snow that packs well into snowballs also will ball up in the soles of a horse's hooves. Shod horses are especially prone to this, as the shoe itself holds the snow. I have seen them teetering along on a buildup 6-8 inches tall. Digging it all out only lasts a little while if they are out moving around in the paddock.
Ice is a killer for horses. My sister's mare shattered a leg playing in the pasture, a ghastly tragedy brought on by an excess of equine exuberance after days cooped up in the barn against an "Arctic Express" bringing -50 wind chill. Shoes with cleats or corks may help with traction but these type shoes can also cause tendon injuries if they stick a fraction of a second too long and over-extend the leg. A horse's hard-surface hooves don't have a lot of natural traction, and slippery shoes just make it worse. Leave off the shoes in the winter for your casual horsemen. If they are travelers in your book, then you need to take into consideration the state of the roads. Are they icy? Frozen into miserable ruts the horses will stumble in time and again? A half inch of powder over ice is a lethal combination.
Extreme cold is dehydrating, so your horses will drink more. They will paw through the ice, or breath on it until they have a tiny little hole just big enough for their muzzles, but they drink less when the water is really cold. This makes them more prone to colic, so make sure your fictional horses have access to lots of water, and have your grooms break out the ice. Please don't try to make your reader believe the poor beasts can survive long on licking frost off the trees or eating snow. They just won't do that, let alone survive.
Being aboard a horse in the winter can be exhilarating but oh so cold. The saddle leather is chilly, the reins are unkind to bare fingers, and your toes freeze if you don't let them dangle out of the stirrups and work them every so often. The wind of your going can freeze your ears right off, so those flapping cloaks in the movies? Nice image. Not so much in practice.
Frost accumulates on a horse's whiskers from its own breath, and they often develop little ice balls in their manes or tails if left outside and ungroomed. Hardy, shaggy ponies will do well, but stable-bred purebreds will have a harder time staying warm and knowing what to do in tough conditions.
Stop and think when putting your fictional equines into a winter scene. If your hero will be slipping on the ice, so will your horse. The "thunder of hooves" on snow is muted, but certainly not soundless, so depending on snow cover to muffle your passage is iffy and makes a whole host of different problems for horse and rider. Travel times will go down, maintenance will go up. Plan your winter journey accordingly, and for Pete's sake, think about the pure mechanics of snow and cold on living critters before merrily trotting off to hunt in the blizzard.
'Til next time.