Sunday, November 14, 2021

The Top Ten Wilderness Survival Skills...Number Five©

 

 


This is the fifth in a series of eleven articles on the top ten wilderness survival skills, things you should know before you go into the wilderness.  To read the previous article go HERE – Author’s Note

 

The Number Five, Top Ten Wilderness Survival Skill: Shelter

 

The number five, top ten wilderness survival skill on my list is,
knowing how and when to take shelter from the elements and why it is vitally important to do so. 

 

The “Rule of Threes”, graphic by the Author.

 

After caring for any injuries, finding a shelter is your next priority when there is a wilderness emergency.  You can only survive for about three hours without fire, or a shelter from the environment.  Shelter comes before a fire, because a windbreak and a shelter make it much, much easier to build a fire.  It is hard to light a fire when you are shivering or the wind blows out your matches, and wet tinder doesn’t burn well!

 

The Why...

 

There are five ways that your body loses heat to the environment, and the “Big Three” are wind (convection), wet (evaporation) and conduction.

 

The ways your body loses heat, from the Search and Rescue Society of British Columbia, HERE.


When it is cold and damp you will need shelter to prevent hypothermia, which is a dangerous dropping of your body’s core temperature1.  And the wind and the evaporation it causes will have a chilling effect and hasten hypothermia.

 

Your first line of defense for temperature regulation and shelter against the wind, the wet, and the cold are your clothes.  Always dress in layers for the worst weather you might encounter.  Maintaining your body temperature in the normal range of 98.6oF (37oC) is your priority! 

 

In addition to your clothes, whenever you go into the woods, you should always bring the means to make an emergency shelter to protect yourself from the cold and the wet.  It might be as simple as a poncho or a couple of large of heavy-duty trash bags, or even maybe, a tent.

 

The simplest shelter is a poncho, here the Author is wearing his Swiss Military Alpenflage Rain Cape, photograph by the Author.


One or two, depending on your size, of three or four mil, 42 to 60-gallon, heavy-duty contractor trash bags will make a good short-term emergency shelter from the wind, the rain, and the cold.

 

The Author in a trash bag shelter, photograph by the Author.


If you can’t find orange trash bags, clear ones are better than black ones, as far as being seen by searchers is concerned.  Black colored or clear trash bags will work, but brightly colored trash bags, like the orange colored ones, are the best because they make it easier to see a misplaced person.2  

 

...Seeking Shelter from the Ground

 

When you sit or lay down on the ground, you will lose body heat to it by conduction.  So, always build a bough bed3 under you to insulate you from the heat stealing snow or cold ground.  Evergreen branches are the best, but you can use anything to make a bough bed.  Whenever you see the word “bough”, remember that you can use other things if they are fine at the tips and no thicker than your thumb at the stem, such as branches with or without leaves, cattails, goldenrod stems, ferns, clover, or grasses.  Whatever you use should be dry, so shake off any moisture or snow on it, before using it for your bough bed.

 

Building a bough bed, based on Bushcraft by Mors Kochanski, step one, building the base.  Graphic by the Author.


In a survival situation, use the Mors Kochanski method of building a bough bed and put bare branches or saplings bigger than your thumb on the ground first, as a base (the straight lines in the picture above). 

 

Building a bough bed, based on Bushcraft by Mors Kochanski, step two, building an insulating mattress of boughs.  Graphic by the Author.


If you are using evergreen boughs, cut off the branches from the base of the tree to the crown, and lay the bottom branches down first, then lay the middle branches down next and finally place the top branches down last.  Put the branches, or whatever you are using to build your bough bed, in a chevron pattern with the boughs making an angle close to 90o on top of the base. 

 

No matter what you use to build your bough bed it is going to compress under your weight, and according to Mors Kochanski, you need to have a compressed thickness of at least 4 fingers, or about 3-1/2 inches (about 9 cm) of dead air space between you and the ground or snow as insulation.  Some experts recommend 2 to 3 feet, or 61 to 91 cm, of uncompressed branches to achieve the necessary compressed thickness.  However, when I conducted an experiment and built a 28 inch, or 71 cm, high pile of balsam fir boughs, it compressed to 18 inches, about46 cm, high under my weight.  So, to get 4 fingers, or 3-1/2 inches (or 9 cm) of compressed mattress, you will have to start with a bough bed that is just over 6 inches, or about 15 cm, thick.

 

...Seeking Shelter Against the Wind

 

Photograph by the Author.


There are a lot of several types of winds that you must take shelter from, storm winds, prevailing winds and offshore, onshore and valley winds.  Understanding how and from what direction they blow is important, especially if you are trying to shelter from them. 

 

Offshore, onshore and valley winds are some of the most common winds and the easiest to predict since they are generated by the daily warming and cooling cycle.  What you must remember about these winds is that at night the land cools faster than the water, the rising warm air over the water pulls the cooler air over the land away from the shore as an offshore or land breeze.  And the air above mountain slopes and hills cools faster at night than the valley air and the warmer valley air rises and pulls the cooler hilltop air downslope and down-valley.  During the day, this cycle reverses.4

 

Since you lose heat to the wind by convection, always try to find a windbreak and stay out of the wind.  This reduces the effects of wind chill and at the same time protects you from wind-blown rain, sleet, and snow.  The lee side of the windbreak, the side downwind, or behind the windbreak, will offer you protection from the wind.  Oh, and remember you must sit between the fire and the windbreak5. 

 

An excerpt from Handbook For Boys, by the Boy Scouts of America, June 1953, page 157.


You can either find windbreaks, like large rocks, fallen trees, or thickets and groves of trees, or you can build them yourself from the materials at hand in the wilderness.  There are two types of windbreaks, solid ones like rocks, walls and logs, and permeable ones like groves of trees and thickets, which are also called shelterbelts.

 

An illustration from “But If You Do Get Lost”, Outdoors USA: 1967, by Kenneth M. Cole, page 91.


The area of wind protection downwind from a solid windbreak is about fifteen times the height of the windbreak.  So, if you build a wall or find a fallen log or big boulder that is three feet or almost 1 meter high, it will block or reduce the wind for about fifteen times the height of the windbreak, which at 3 feet, or almost 1 meter, will be 45 feet or just over 14 meters.

 

In the winter, a solid windbreak that is three feet or almost 1 meter high, will create a snow-drift zone downwind of the windbreak, equal to the height of the windbreak times five, which in this example is 15 feet or almost 5 meters, long.  However, the area behind, or in the lee of, the windbreak out to about 6 feet or 2 meters, which is a distance equal to two times the height of the windbreak, should be mostly drift free. 

 

A grove or stand of trees also acts as a shelterbelt or permeable windbreak and when the wind blows through a grove of trees, with a vegetation density of 50 to 60%, the wind is both forced over and through the trees.  The trees will block and slow the wind for at least fifteen times the height of the grove6, which if it is 30 feet, or almost 10 meters tall, will extend downwind from the edge of the grove for 450 feet, or almost 135 meters.  This wind reduction can be as much as 70% within the first 100 feet, or roughly 30 meters, dropping to 50% out to 200 feet, or 60 meters, from the downwind edge of a grove of trees. 

 

During the winter, if you are downwind of an approximately 30 foot or almost 10 meters tall grove of spruce trees, the wind and snow will create a drift zone downwind of the trees that can extend as far as 150 feet to 300 feet, or about 45 to 90 meters.  This distance is the height of the grove of trees, times a factor of five to ten. 

 

So, during the spring, summer or fall, the best type of windbreak is a thicket or grove of trees, and the best spot for protection from the wind, would be somewhere within five to ten times the trees height, downwind from the edge of the grove.  However, during the winter, the best spot to avoid snow drifts would be downwind about ten times the trees height away from the downwind edge of the grove.  This spot will give you the best protection from the wind and it will also put you beyond the snow drift zone.  You can also build your own windbreak, downwind from a grove of trees and combine the best of both windbreaks

 

So, in a wilderness emergency take shelter from the wind, the wet and stay off the cold, cold ground!

 

Don’t forget to come back next week and read “Pumpkins...Boil ‘em, Mash ‘em, Eat ‘em in a Stew!©”, where we will talk about the history of pumpkins and what you do with your left over Halloween decorations.

 

Photograph by the Author


I hope that you continue to enjoy The Woodsman’s Journal Online and look for me on YouTube at Bandanaman Productions for other related videos, HERE.  Don’t forget to follow me on both The Woodsman’s Journal Online, HERE, and subscribe to BandanaMan Productions on YouTube.  If you have questions, as always, feel free to leave a comment on either site.  I announce new articles on Facebook at Eric Reynolds, on Instagram at bandanamanaproductions, and on VK at Eric Reynolds, so watch for me.

 

That is all for now, and as always, until next time, Happy Trails!

 

 

Notes

 

1 Don’t forget that when it is hot, you will also need a shelter from the Sun, because hyperthermia, an elevated body temperature, the opposite of hypothermia, can be just as deadly.  And the wind, and the evaporation it causes, are also an enemy, because when it is hot it will dehydrate you.  So, if you are going to be in a hot and dry area always bring a tarp or some way of building a Sun shield, and don’t forget that at night deserts can get very cold.  For more on desert survival read “Desert Survival: Information For Anyone Traveling In The Desert Southwest, 1962 ©”, HERE.

 

2 For more on how to use a poncho or trash bag as a shelter read, “Using your poncho or a trash bag as an Emergency Shelter ©”, HERE.

 

3 Bough beds are also called ground beds, bush beds or browse beds and have been used by travelers in the wilderness for centuries to insulate themselves from the heat robbing ground.  For more read “Making an Emergency Bough Bed©”, HERE.

 

4

An excerpt from Weather, by the Boy Scouts of America, page 9

 

For more on the wind and the other four W’s that you have to watch out for when in the wilderness, read “Woodcraft 101: Putting Up A Tent ©”, HERE.

 

5

An excerpt from “But If You Do Get Lost”, Outdoors USA: 1967, by Kenneth M. Cole, page 91.


 For more information on windbreaks read “...Seeking Shelter Against the Wind©” HERE and “But If You Do Get Lost”, Outdoors USA: 1967©”, HERE.

 

6 The actual area of wind protection, downwind from a grove of trees, is between fifteen to twenty times the height of the trees.

 

Sources

 

Boy Scouts of America, Handbook For Boys, [Boy Scouts of America, New York, New York, June 1953], page 157

 

Boy Scouts of America; Weather, [Boy Scouts Of America, Irving, TX; 1992], page 9

 

Search and Rescue Society of British Columbia, https://www.sarbc.org/hypothermia, accessed November 2, 2021

 

United States Department of Agriculture, Outdoors USA: 1967 Yearbook of Agriculture, [United States Government Printing Office, Washington, DC, 1967], p 87-89, https://archive.org/details/yoa1967/page/n3, accessed November 2, 2019

 

 

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