Tramping  Safe travelling in the sub-alpine zone

Heading beyond the bush-line? What do you need to know, and practice, to travel competently and with style?

In mountaineering parlance, the ‘death zone’ refers to the altitude zone above 8000 metres, where the margin of error between life and death rests on a knife edge. In Aotearoa New Zealand, we have our own death zone at a much more modest altitude, but equally as treacherous – the subalpine zone – that occurs between about 1200 and 1500 metres, depending on the latitude. This semi-vegetated zone exists in a band above the bushline, but below the permanent snowline, and is variously referred to as the transalpine, subalpine, snowgrass or alpine zone, monkey-scrub belt, leatherwood leisure park, or carpet grass alley.

A significant number of backcountry accidents, fatalities and injuries occur in this subalpine environment, and many of them are preventable. Backcountry Accidents has formed a technical sub-group to suggest strategies for moving through this zone safely. Collectively, this group has spent thousands of days travelling in the subalpine zone, through the most rugged and remote parts of the country. This hard-earned knowledge is offered here in good faith, and in the hope that it may help avoid future accidents.

Attitude

 Modesty and humility are the crucial states of mind for the mountains.

Just because the sublapine zone is vegetated, and not permanently covered in snow or ice, does not mean that travel through it is not a serious undertaking, sometimes requiring mountaineering skills. People often underestimate this zone, simply because they view it as a place to ‘pass through’ in order to reach the place of real adventure. It’s a mistake, however, to think that mountains only get more dangerous as you go higher; a 50-degree snowgrass slope is just as treacherous as a similarly angled snow slope. In fact, each different altitude zone requires a different skill set. Many approach routes pose more danger than the summit climb itself. Learning good skills requires sound observation skills, an ability to reflect, and a careful approach to building and consolidating your experience. Transalpine travellers need to critically assess the risk and acknowledge their own abilities. Always be open to advice from more experienced people.

Turning back is often harder than going forward.

New Zealand mountains (and rivers) demand conservative decision-making. Be prepared to re-route an entire trip rather than risk ten metres of bad terrain. Sit down, eat, drink, and then consider all the relevant factors, taking time to objectively consider the facts. Don’t allow desire to overrule judgement. If you turn back, accept it as a valid decision made at the time: ‘I like being a wuss who is still alive’.

Be prepared

Gear. You will always need storm gear and often an ice-axe and crampons. During spring, or after warm nor-westers, when little snow is visible, people assume they won’t need snow gear. Leaving these tools behind is appealing, because it lightens your load. However, snow wedged in a steep gully can ice up overnight, and be lethal to the tramper attempting to cross it. A light ice-axe and possibly crampons can mean avoiding a fall, or arresting a slip quickly.

Consider your group capabilities. Is everyone capable of crossing hard, frozen snow slopes with heavy packs when they have not been in crampons for a while? Is it better to wait until after the sun has softened the snow? Weigh this up against the increased risk of snow sloughing or avalanching enough to cause a significant fall. When travelling on snow-grass slopes, positively edge your boot into the uphill side of the tussock near the root, not on the leaves – these are very slippery, especially when wet, snow-covered or extremely dry.

Thinking through the consequences

Where do I end up if this goes wrong? If certain death awaits below, do a lot more thinking. Be cautious even crossing something within your capabilities if the consequences are likely to result in a significant fall. You may make a considered move across an awkward section if there is something close below to stop you, but make a careful assessment first. Don’t just assume it will halt a slip or fall.

Manage the critical times in the mountains when the risk is immediate and real.

Heuristic traps

Just because a route is detailed in a guidebook, or you know someone else has travelled over it, does not necessarily mean that your party can. Traversing steep snow-grass is a specific skill, much like rock climbing; it requires an understanding of balance and how to weight your body and feet. A classic heuristic trap occurs when a group travelling across an innocuous tussock slope is lulled into a false sense of security when faced with a narrow, steep snow tongue that separates them from the next alluring tussock slope.

Conditions

Danger in the subalpine zone is very dependent on conditions. Sometimes wet conditions make things very slippery, while at other times wet soil moulds or supports your boot better. Pay particular attention to damp or wet rock covered with moss or lichens. Frost and ice slicks on boulders or scree slopes can sometimes look dry and safe.

Gauge and calibrate reality to the conditions rather than your perceptions.

Equally, dry can be good but during late summer an increase in dead snow-grass leaves can make conditions very slippery. Snow on snow-grass is worst of all. Move with caution, using an ice-axe as needed. Keep your other hand free to grasp exposed tussock.

Adverse weather conditions above the bushline heighten the risk of hypothermia. While reaching that sheltered place may take only 10 minutes in good weather, during a storm it could take an hour or more. In such situations, it takes skill to assess the abilities of the whole party. Base your decisions on an honest reappraisal of your party, your speed and the conditions.

Resolving unknown tramping and climbing obstacles can quickly go from exciting to anxious with a sudden change in conditions, weather or terrain. Be observant of yourself, your group, your surroundings and the changing conditions. Recognising your predicament early, changing plans or turning back can fully test the mettle of your party.

Skills

Use two points of contact, or three if necessary, to make each step secure and reversible.

Your ice-axe and crampons work well on snowgrass and rock. Don’t be precious with your gear, it’s designed for more than just snow! On steep ground, say climbing up the Waterfall Face in Mt Aspiring National Park, you can use the pick to secure a handhold. In other situations, the ferrule may help to secure balance. There are several lightweight axes now available in the 70-80cm range, which are not much of a burden to carry even if they’re not needed. Beware, however, of using short ice-axes; they can cause you to overbalance. Walking poles can likewise help with balance on slopes, and provide support when crossing rivers. But beware of relying too much on them in snow, as they are no substitute for an ice-axe when you may need to self-arrest. Unless the slope is very benign, don’t bum slide, but instead walk facing sideways and using the edges of you boots. When sidling in tricky country, remember natural features often repeat. If it is steep and slabby on the other side of one spur, the next one will probably be the same. Expect it, or head somewhere different.

Travelling on steep ground in dim light carries more potential traps. Balance is affected as eyes adjust to black and white vision. Check the stability of rock, one hold or step at a time.

If gear falls away down slopes, remember safety first before you run after it. If you have to watch it bounce down bluffs, let it go.

Check out potentially dangerous slopes first by sending someone to scout ahead without the burden of their pack. If the ground is too difficult, use protection, or go somewhere else.

Consider using crampons on steep, hard earth, rock or slippery vegetation. Dangers include catching them and ‘balling’ up, but it works safely enough if you are thinking about every step.

Ropes and belaying

A rope can be useful in the subalpine zone, but solid anchors are rare. You also need to weigh up the benefit of the rope against the risk of insubstantial anchors and the extra time needed for belaying. Before setting up anchors, think about the route beyond. Where is it taking you? Are there other safer or easier options?

Anchors in the subalpine zone include snow, rock, earth or vegetation. The need (handrail, pack hauling or belaying) can dictate the anchor. Belaying below a stake or ice-axe driven into earth (and tied off at ground level) can be very effective.

Leading in the sub-alpine zone

Know the different skill levels in the party before your trip. At awkward sections let the party telescope up a little, so that the less confident members have nearby security and support. Someone who is strung-out and alone is much more at risk of an accident. Place the less able just behind the leader so they can follow step by step, and that will speed the party up. Very few leaders do this effortlessly and comfortably, yet it is one of the most important ways to reduce accident potential and understand the competence of the group.

When in front, keep aware of how each person copes with the terrain. Someone who is struggling may be affected by all sorts of factors:

  • Less fit, feeling exhausted or needing food and water
  • Less aware of the environment
  • Less able to pick good micro-placement for their feet
  • Spacial or balance problems
  • Sight problems because of near/far sightedness or misted-up/rain affected glasses; vision and balance are interconnected
  • Has inferior boots or other gear that affects their pace.

Confident people usually have more experience and more commitment, and have often chosen gear for the particular type of trip, such as specialist boots. Those in front can easily sidle safely in quality boots with good edges. They may be too preoccupied with forging ahead to consider that others may have inadequate boots that roll underfoot, or have poor tread.

Being ‘hard’ and ignoring these issues does not make the party faster; it often creates a desperation to keep up, thereby increasing the risk. The front runner should chill out a bit, stop being driven by trip-failure anxiety and start thinking about the best line for the less capable in the party. As a leader or friend, keep it in mind; work together.

Route finding

Look ahead at the big picture, and try to choose routes to avoid trapping yourself.

When at a good vantage point, identify main features and scan for slips, gullies and bluffs. Calibrate your altimeter earlier in the day to a known height for later use. At a decision point, when you have temporarily lost the route:

  • Stop and confer using the map and route-guide for added information.
  • Consider all your options and weigh them for likelihood of success.
  • Agree on someone scouting ahead, the scouting time and the re-grouping point.
  • Return to your LKP (last known point of route) then zig-zag to relocate the track or route.

Route-finding:

  • Use any prominent landmarks, trip notes, map and altimeter for reference at decision points. Time spent planning avoids time lost on the wrong route.
  • During an ascent, look back periodically to recall specific features for the descent.
  • Ensure that you can safely descend what you climb, or plan to use an alternate descent route.
  • Place a small cairn at a critical decisionpoint (but avoid excessive cairning).

The ‘big three’ of avalanche terrain features can also be useful for summer tramping and climbing:

Incline: pick a route with a reasonable run-out in case someone falls, rather than one with a bluff below. This applies particularly to snow slopes and crevassed glaciers.

Aspect: snow conditions can vary with aspect from slush to green ice. The majority of snow slope accidents happen when hard ice or slush conditions exist.

Elevation: use landmarks, notes, map and particularly the altimeter at height decision points.

Rock Fall

Observe where rocks regularly fall, as fresh stones will indicate. Rock slides and slips are often used as a way up through bluffs, but further rock fall is a risk. Most rock fall happens in storms, rain and wind, or when frost thaws. If carrying helmets, use them, and do not linger.

Sometimes rocks fall unpredictably and randomly. However, a common cause of rock fall is when other people accidentally dislodge loose rocks above. The risks of fatality or injury are reduced by wearing helmets, keeping the party close together, having spotters, and regrouping at sheltered positions.

Finally, travel in the subalpine zone does pose risks, but done with care and thought, can be especially rewarding.

If you want to be totally safe, stay in bed and avoid cars.

(Johnny Mulheron thanks the Backcountry Accidents subalpine zone technical sub-group: Shaun Barnett, Erik Bradshaw, Robin McNeill, Geoff Spearpoint and Geoff Wayatt.­­ This article first appeared in the FMC Bulletin – November 2015)

Wilderlife