[pct-l] "What's Under the Snow" (part-2; long)

[Jim Faris]

good article  thank you
 

    On Sunday, November 6, 2016 4:06 PM, "ned at mountaineducation.org" <ned at mountaineducation.org> wrote:
 

 "What's under the snow" (part 2)

 

"Why should I care or even need to be aware of this?"

It will change how you walk over it!

 

For the snow-hiker wearing regular shoes or boots and not using snowshoes or
skis, what is under the surface of the snow is a big safety issue!

 

As we discussed earlier, there are multiple layers of soft snow, hard snow,
wet-frozen snow, and ice, all peppered with wind-blown debris from pine
needles and pine cones to branches and entire trees shattered by winter
avalanches. With this in mind, let me illustrate exactly what your feet will
have to deal with to keep from slipping.

 

The biggest danger shows up on the steep slopes (an incline of the terrain
that looks like a great sledding hill or steeper), whether you're going up,
down, or across them. When the snow isn't flat, it is easy to simply slip on
the surface, fall, and tumble into a tree, boulder, or lake below. What can
cause you to lose your "edge" or the grip of your shoes on the snow and what
do you do about it?

 

Premise:

 

Most snow-hikers can walk on flat snow no matter whether it is soft, as in
powder snow, or hard, as in springtime consolidated snow (the kind most
early-season hikers will be walking on). They just slow down and are careful
about how and where they place their feet. They find out quickly they can't
push off their toes, as on dry ground, because they'll just slip in place.
So, they adopt a kind of "flat-footed" foot placement of each step. Any
other kind of broad, flat application of their foot to the snow results in a
slip.

 

Most of the comments below pertain to springtime consolidated snow and not
wintertime powder snow where avalanches can be easily triggered by the
tracks of the hiker across steep slopes. Avalanches are not a concern for
hiking on springtime, sun-consolidated snow typical of what most long trail
thru hikers will face. However, if new powder snow greater than a foot-deep
falls on old consolidated snow while you're out there, avalanches can and do
happen. Learn what to do to maintain your personal safety should this occur
while you're out there.

 

Most of the comments below are to snow-hikers who are making their own route
across the snow and not following in the boot-tracks of others. This is an
important detail that most summer hikers don't understand about snow-hiking.
If you like where the tracks in front of you are going, by following or
walking in them, you'll be able to step onto a flat, side-to-side path that
doesn't require you to edge with your shoes. You can almost walk normally!
Realize that compressed snow is warmed snow and will freeze at night,
glazing over, and be slippery in the morning to walk on. You can use simple
microspikes in this situation to maximize your grip.

 

So, if you are heading up into the mountains later in the snow season or
summer hiking onto the snow where it is still at high elevations early in
the summer season, you probably don't need hiking crampons. However, you've
got to stay in the boot-track on those microspikes. If you don't like where
the footprints are going and you want to make your own route over the sloped
snow, realize that microspikes tend to roll off shoes when on hard snow on
steep slopes and down you'll go!

 

When the terrain tips on edge and everything is sloped ahead, is where most
people fall. Of course, some can slip and fall while standing up and others
can fall after postholing, but most injuries occur after slipping on an
incline. Now, what factors contribute to slip-and-falls? (This is where the
layers in the snow beneath the feet and the shoes you're wearing come in!)

 

Traversing on various snow layers:

1. The surface of the snow is hard, maybe frozen from the night before. You
can be wearing the best and most appropriate shoes for the task and still be
slipping all over the place. The only solutions for safe walking on this
type of snow layer is to choose another route around it or to apply traction
devices (hiking crampons or microspikes) to your feet to increase the grip
of your shoes on the snow. If the snow slope is steep, you'll be on the
edges of your shoes (if there isn't a boot-track to walk in that has a flat
bottom) and I'll talk about this below.

 

2. The lugs on the bottom of your soles are so worn down so they can't get
much of a "bite" into the snow (hard or soft). The lugs on your shoes and
their pattern are crucial to your ability to move on snow. They need to be
deep, sharp-edged and not too close together so snow can get in between
them. This is just like car tires designed for snow (versus mud or dry
pavement). Too much and too little rubber too close together and you'll just
slip and fall.

 

3. The rubber on the bottom of your shoe needs to be on the hard vs. soft
side so it can bite into the harder snow surfaces. Soft lugs will "roll" or
flex when standing on hard surfaces. On snow, this is not a good thing as
the shoe can move when you don't want it to and down you go.

 

4. The sole, itself, needs to be firm, side-to-side, so you can stand on its
edges on a steep hill and not have it compress into a rounded curve,
allowing a greater surface area to be in contact with the hill and the shoe
to lose its edge and slip. The sole should easily flex forward, as in
walking, but not allow itself to be twisted, heel to toe.

 

(You know those shoe-testing ramps in some stores? Take your new shoes onto
that ramp, stand sideways to the slope, then throw your knees and ankles
uphill, into the slope so that you're standing on your shoe's uphill edges.
Do the edges compress into a soft little curve? If so, those shoes can't be
relied upon to hold an edge on hard, frozen snow and keep you from falling.
This will be a concern you don't need when trying to enjoy your snow-hike,
whether thru hike or spring weekend trip with your friends).

 

5. The surface of the snow (doesn't matter how thick) is soft, but there is
an ice layer beneath it that you are walking on. You cannot see what you're
standing on. Your ability to make your shoes "bite" or edge into this layer
while traversing is the key to your safety and confidence. It's all about
the "feel" of your shoes into the surface you're standing on. Good boots
that can edge well may be able to get enough of a bite into the surface to
hold you to the hill with each step and get you across this kind of slope
safely. Adding hiking crampons to get a better bite will aid this bite, but
the teeth have to be close to the edge of the shoe (thus, microspikes don't
work on this kind of slope as well as crampons).

 

6. Flat-footing your steps across a questionable slope isn't enough to get
your shoes to bite into the surface conditions. Here is where the skill of
"kicking" each step into the hill greatly increases your shoe's ability to
get a good bite and hold you to the hill. Be aggressive. Be determined to
create a platform for each step that makes you feel confident that you can
stand stable on each foot as you go across the slope. Initially, you haven't
felt all these feelings from your feet, but over time and with experience
you will understand what's going on down there and what you need to do to
traverse a slope safely, no matter the surface conditions. Risk awareness,
risk assessment, and patience are key! You will learn, but don't be hasty
until you know what your feet and shoes are saying about each slope!

 

7. Realize that stepping into the posthole made by the person in front of
you doesn't mean that you won't posthole deeper (depending on your weight
and how hard you stepped into that hole). Unfortunately, we have seen
snow-hikers do this, posthole more, lose their balance, fall, slide into a
tree, and need to be flown to a hospital, ending their trip.

 

Descending on various snow layers:

1. Going downhill you can fall quite easily, depending on the snow
conditions and layers in the pack! If the snow is icy or frozen on top, the
safest way down is to crampon-up and cut a descending traverse while
well-balanced with two poles, one of which is a self-arrest pole. You can
glissade, but your pants may get pretty torn up.

 

In these conditions, hiking crampons are better because their teeth are
closer to the edges of your shoes allowing you to use them while your shoes
are still on-edge. Microspikes, or traction devices made of chains and
teeth, do not get much of a bite into the hard or frozen snow when your
shoes are on-edge because all there is in that location on your shoe are
chains. Any other kind of traction device, whether instep only, heel and
instep, or ball-of-foot, usually doesn't have enough teeth out on the edge
of the shoe to allow it to be used on-edge nor does its frame wrap up
alongside the foot (a big deal!).

 

2. If the snow is soft on top, but has a frozen layer beneath that holds
your weight without postholing, glissading is the safest way down and a
whole lot of fun! You can still cut a descending traverse with nice boot
"purchase" or bite, especially if you utilize microspikes or hiking crampons
to hold each step to the hill.

 

3. If the snow is really soft and you're postholing with each step,
glissading may be out of the question because when you sit down in the snow
you just make a big hole that won't let you slide. There may, yet, be
another ice layer deep within the pack that is holding you up. Test it with
aggressive steps to see if you'll slip at all (of course, always at the
ready for a fall with your poles placed way out to the sides of you to
maintain your balance with one being a self-arrest pole to stop any tumble).
Cut a descending traverse or do a heel-plunge while wallowing your way down
to the snowline. Be very careful not to posthole, loose your balance, and
fall while your leg stays in the hole (envision your leg in a hole to your
knee and your body twisting and falling sideways). This snow condition can
seriously injure your knees. I'm sorry, my friend, but you got there too
late in the day or season!

 

Here are a few skills you'll need to employ to maximize your fun and safety.

- Heel-Plunge: This is where you can walk straight-legged straight down the
fall-line using the heel of your shoe as a brake. Your security in doing
this skill is greatly increased if you have shoes with vertically-faced,
pronounced heels (think of the old-style, two-piece Vibram soles on
traditional hiking boots. Stay away from one-piece, soft molded soles with
rolled edges.they just turn into skis!).

 

- Glissading: This is the safest way down as you're already sitting and less
prone to fall, but you can lose your alignment, feet-down, and spin or
tumble into hazards below. You must learn how to maintain your alignment and
speed and be ready to self-arrest.

 

- Descending traverse: This is where you do straight-legged plunges down and
across the slope edging with each step. Takes a little practice and shoes
that have high tops you can leverage into the slope (as with all edging).

 

- Boot-Skiing and Skating: This technique is for those who have great
balance control and like to slide on their feet! It can be done under just
the right snow conditions slope, so there has to be a subjective assessment
of the snow and a personal performance readiness before you launch yourself
down the hill, be it a small drift or a large snowfield. It is a great deal
of fun and once you master it, you'll be seeking every opportunity you can
find play with it!

 

Ascending on various snow layers:

1. If the consolidated snow is hard and frozen or just crusty, you've got to
check while at the bottom of the slope whether your choice of footwear will
get much of a bite into the hill, whether on edge or toe. The safest way up
is to go straight up wearing hiking crampons or microspikes with two poles
pushing from behind you and spread out a bit. Go slow. Stay balanced. The
next best way is to cut an ascending traverse, a series of switchbacks, if
you will, up the slope, but you'll have to either kick aggressive steps to
make platforms for each step (takes a ton of time) or wear your crampons and
edge your way up, kicking and scratching platforms as needed.

 

2. If the snow is soft on top with an ice layer beneath, it will be pretty
easy to kick steps, toe into the hill, straight up the slope, just test
whether the compacted footprint you're making will slip on the ice layer
beneath. Again, wear microspikes or hiking crampons to increase your bite
into the hill and kick toe-in platforms with your heels held higher than
your toes. This is a big deal! When you load that platform by standing on
it, your heel might compress into the snow, become lower than your toes, and
slide out of the hole backwards causing you to fall.

 

Most people will cut an ascending traverse up the hill since the snow allows
for the making of great "buckets" for your feet to stay flat, side-to-side,
and you to feel the most comfortable, confident, and secure.

 

3. If the snow is super-soft and you've had to posthole all the way up to
the base of the climb, going up the hill is going to be a "wallow-fest" of
floundering and exasperation! If you can do it, great (the climb is short
and you have the energy), otherwise consider spending the night right there
and allow the cold night to harden the snow for an easier and safer ascent
come early morning (say at 0500, a hour or two before the sun hits the
slope).

 

Synopsis:


. Knowing what's in the snow will dictate the skills and equipment you use
to maintain your safety while walking over it.

. You must constantly assess the character or ability of the snow to hold
your weight and that of your shoes to maintain traction and edge in changing
snow conditions, from sun to shade, new snow to old, and on various degrees
of slope. This is being "snow-savvy." Based on this information and the
awareness of dangers downslope that you could slide or tumble into, you can
make informed decisions about how and whether you want to cross a particular
snow drift or field.

. Learn how to do all this before you're on your own. Attend a snow skills
course where someone can let you feel what the various layers in the snow
are like and teach you how to stay safe on them!

 

C 2016 Mountain Education, Inc.

 

 

Ned Tibbits, Director

Mountain Education, Inc.

ned at mountaineducation.org <mailto:ned at mountaineducation.org>  

 

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