One of the best things about raising bison is that the ranch never looks the same two months in a row. The herd's year follows the seasons, and in the Bitterroot Valley, the seasons are hard to miss.

Here's a walk through a year on the ranch, from the first calves of spring to the deep quiet of winter.

Spring: new life and shedding coats

Spring is when the pasture starts turning green again and the herd starts to look a little scruffy.

As the weather warms, bison shed their heavy winter coats. It doesn't happen neatly. The old fur comes off in big patches, and for a few weeks the herd can look downright ragged. You'll often see them rubbing against fence posts or trees and rolling in their dirt wallows to help the process along.

Spring is also calving season. Bright orange calves, the ones ranchers call "red dogs," start showing up in the pasture, usually staying very close to their mothers. For a growing herd like ours, it's the most exciting time of year.

On the ranch: checking the herd quietly and often, keeping an eye on new calves, and watching the pastures as the grass comes back.

Summer: green grass and the rut

Summer in the Bitterroot is long days, big skies and grass as far as you can see. The herd spends much of the day grazing, and the calves grow quickly.

Mid-to-late summer is also the breeding season, called the rut. This is when bulls become much more active and vocal. If you've never heard a bison bull bellow, it's a deep, rumbling sound that carries a long way. Bulls wallow, posture and compete for attention, and the whole herd gets a little livelier.

On the ranch: managing pastures so the grass stays healthy, keeping water available in the heat, and giving the herd extra space during the rut.

Fall: thickening coats and golden light

As the days get shorter, the bison's winter coat starts coming in thick again. By late fall, they look full and heavy, ready for what's coming.

Fall is also one of the most beautiful times in the valley. The cottonwoods along the river turn gold, the light gets low and warm, and the first snow appears on the peaks of the Bitterroots. The calves from spring have darkened from orange to brown and are starting to look like little bison instead of little red dogs.

On the ranch: preparing for winter by checking fences, planning feed and water, and making sure the herd goes into the cold season healthy.

Winter: snow on their backs

Winter is when bison show off what they were built for. Their coats are so well insulated that snow can rest on their backs without melting. They face into storms, sweep snow aside with their heads to graze, and slow down to save energy.

It's quiet on the ranch in winter, but it's not easy. Keeping water open, providing supplemental feed when the snow is deep [CONFIRM WITH FAMILY] and watching the herd every day keep us busy through the coldest months.

On the ranch: water, feed, fences and daily checks.

And then it starts again

By the time the snow starts melting off the pastures, the herd is shedding again, the grass is starting to green up, and somewhere out there, the first calf of the new year is about to arrive.

That's the rhythm of the ranch. We've only been at this a few years, but already it's hard to imagine our lives following any other calendar.