It’s easy to define, yet it eludes description. It’s common in springtime – entire mountainsides can be covered in it – yet often maddeningly hard to find. It can be completely safe – and deadly.

Once you understand it, you can rack up thousands of vertical meters in a morning. Yet millions of skiers never experience it. It can be bone-jarring, tooth-rattling and knee-popping to ski on. But when it’s good, first-timers routinely say it beats deep light powder.

Corn snow. Firn Schnee. Sulz.

Whatever expression you use, it makes skiing in the springtime extra special.

We’re definitely not talking about knee-deep slush bumps or churned-up pistes. That may be what many skiers think of when they hear “corn snow”. But that stuff is for teen-agers.

Real corn snow is entirely different.

Defining corn snow – “Firn Schnee” to Germans and Austrians, and “Sulz” among the Swiss – is easy. It’s a thin layer of melting snow lying atop a solid crust formed by several diurnal (day-and-night) melt-freeze cycles caused by warm sunny days and cold clear nights. The sun being a key ingredient, the melt-freeze crust is formed on sun-bathed slopes.

What does corn snow feel like to ski on? Here’s the hard-to-describe part. Sherbety. Buttery. Creamy. These are commonly heard analogies. But none does it justice.

Corn snow is moist but not wet. Grippy and supportive but not sticky. Fast but not slippery. Crisp but not hard. Forgiving, providing a soft feeling of sinking in. Yet one’s tracks are hardly more than a couple of centimetres deep. (If left alone, in fact, one day’s corn snow tracks will be all-but invisible the next day.)

Corn snow is endlessly accommodating. Big turns, little turns, carved turns, skidded turns, hard turns, lazy turns or no turns – you can do it all.

And easy. If it’s good corn, a solid intermediate can handle a 40-degree slope. Yet it’s still challenging. Some of the steepest lines taken by mountain guides and other experts all season will be on corn snow.

Most of all, corn snow is unbelievably fun.

Because the verbal description never comes close to depicting the experience, a person’s first real corn snow is often a jaw-dropping revelation.

Real corn snow is found away from the pistes and lifts. Often it’s hidden from view, tucked behind a rocky ridge or rolling shoulder. Other times, it hides in plain sight, a broad slope falling away from a lift or running out to the side within reach via a traverse or short ascent.

But because it’s no longer powder, most people don’t bother with it – it must be terrible skiing. Or, seeing debris from a recent wet-snow avalanche, they assume it’s dangerous. But dedicated corn-seekers will gladly go touring in search of it.

The spread-out lift systems we have in the Alps access enormous terrain areas amenable to springtime corn snow.

Snowboarding and the Freeride Revolution have made great corn snow harder to find, however. Today’s fat planks make it easy to ride corn snow after it has had too much sun, leaving deep slush ruts that become welded into place during the next night’s freeze, destroying the slope for everyone.

Luckily, one can still find great corn – including off the lifts in Disentis, Sedrun and Andermatt. More on that in my next post.