At their best, ski glades are forests with exceptional skiing possibilities. At worst, they are ski trails with damaged and dead trees in the way. They are very different from conventional ski slopes. Unlike those treeless mountainside swaths you can see from the highway, ski glades are mostly forested, with narrow, open lanes tacking among the trees. Some glades are open groves of trees occurring naturally in the wild backcountry. Others are purposefully developed by ski resorts – often within the woods between their existing treeless trails. These are usually made by removing most of that forest’s understory vegetation and leaving a scattering of the larger overstory trees. In fact, even natural glades sometimes get “brushed out” by local enthusiasts, because, while skiing in the woods is always fun, it’s more enjoyable without being slapped by brush and branches.
However they’re started, all glades change with time and use. Regrettably, they tend to degenerate due to poor vegetation management, overuse, or both. What begins as a single ski line – a series of linked, single-track short-radius turns downslope through the woods – soon becomes an increasingly thin forest and eventually a full-on slope, as ever more skiers seek out their own lines through those same woods of ever fewer trees. It happens faster than you might think, too.
Why? Because glade trees are frequently damaged, cut, and killed by skis and saws alike. Ski edges can do real damage to tree bark, and they can be fatal to the growing tips of small trees protruding through the snow. What’s more, skiers themselves can be awfully hard on branches and smallish trees that interrupt an otherwise good ski line. Yes, some zealots ski with folding saws. And remember, mountain forests are particularly vulnerable, growing in relatively harsh conditions at high elevations on steep slopes and thin soils. Further change often follows. Storms of snow, ice, and cold break and topple trees. With too few trees holding them, soils erode, even slump, during summer rainstorms. Species go missing. It happens in natural glades if they are overskied or brushed out excessively. And it has certainly occurred at developed resort glades where only a single canopy of scattered big trees was left initially and is now overskied and dying back – with no understory of replacements.
Bad as they are, these consequences are not just for the woods. Poor design, overcutting, and overuse of glades all compromise the trees, and they can ruin the skiing, too. This leaves foresters, resort managers, permit-grantors, and renegade woods skiers all wondering the same things: how to create good glades – skiable steeps with enough trees to catch and hold blowing snow, but with enough space to ski. And how to make them last. If all that pesky understory vegetation is removed, or only the pretty paper birches are left, how long will the glade be a glade?
It’s largely a question of tree density or spacing. Generally, more trees remaining in the woods is better for the woods, and more space between trees is better for most mere-mortal skiers. Where’s the balance? Each forest is different. In most northern hardwood and mixed-wood glades, a sustainable ski glade will look something like a recently thinned stand; there will be extra space between the remaining trees. There will be some scattered large trees, but among them there would also be an ever-increasing number of smaller-diameter trees.
Spruce-fir glades are very different. Their trees tend to have narrower crowns and can grow well at closer spacing. They usually grow in even more harsh conditions at yet higher elevations and worse weather. As a result, they often regenerate in waves of seedlings following windthrow and breakage events. In such high-elevation softwoods, expect a tighter glade and accept that some areas will have to be allowed to regenerate – roped off and unskied for years at a time.
Because even dense glades gradually become more open, good glade management in any stand type should err toward higher tree density. Equally important are their types and sizes. Healthy, lasting glades contain islands of intact forest pieces. These islands should contain a full complement of naturally occurring tree species, ages, and sizes, and they should be unskied – at least for the time being. Forest islands should be diamond or tear-shaped, pointing uphill. Around these islands are ski lines, and these lines themselves should not be completely devoid of trees; some scattered trees should remain, and they should be of good health and a mix of species and sizes.
If you’re managing your own woods for skiing, find and mark good, skiable woods lines in winter. In summer, consider how to open those marked lines. Ease into it. Learn to recognize areas that need little alteration – where simply cutting some striped maple and hobblebush in combination with some light pruning of tree branches is all that’s needed to create a good, skiable line. Whatever stumps you do make, make them low and flat. High, pointed stumps are nasty, especially when hidden by powder. Resist the temptation to remove all but a few scattered big trees – there’s no future in it.