FM 3-05.70 Field Manual Survival (17 May 2002)

13-13. The temperature of desert sand and rock typically range

from 16 to 22 degrees C (30 to 40 degrees F) more than that of the

air. For instance, when the air temperature is 43 degrees C (110

degrees F), the sand temperature may be 60 degrees C (140

degrees F).

13-14. Intense sunlight and heat increase the body’s need for

water. To conserve your body fluids and energy, you will need a

shelter to reduce your exposure to the heat of the day. Travel at

night to lessen your use of water.

13-15. Radios and sensitive items of equipment exposed to direct

intense sunlight will malfunction.

WIDE TEMPERATURE RANGE

13-16. Temperatures in arid areas may get as high as 55 degrees

C (130 degrees F) during the day and as low as 10 degrees C (50

degrees F) during the night. The drop in temperature at night

occurs rapidly and will chill a person who lacks warm clothing

and is unable to move about. The cool evenings and nights are the

best times to work or travel. If your plan is to rest at night, you

will find a wool sweater, long underwear, and a wool stocking cap

extremely helpful.

SPARSE VEGETATION

13-17. Vegetation is sparse in arid areas. You will therefore have

trouble finding shelter and camouflaging your movements.

During daylight hours, large areas of terrain are visible and

easily controlled by a small opposing force.

13-18. If traveling in hostile territory, follow the principles of

desert camouflage:

• Hide or seek shelter in dry washes (wadis) with thicker

growths of vegetation and cover from oblique observation.

• Use the shadows cast from brush, rocks, or outcroppings.

The temperature in shaded areas will be 11 to 17 degrees

C (52 to 63 degrees F) cooler than the air temperature.

• Cover objects that will reflect the light from the sun.

13-5

13-19. Before moving, survey the area for sites that provide cover

and concealment. You will have trouble estimating distance. The

emptiness of desert terrain causes most people to underestimate

distance by a factor of three: What appears to be 1 kilometer (1/2

mile) away is really 3 kilometers (1 3/4 miles) away.

HIGH MINERAL CONTENT

13-20. All arid regions have areas where the surface soil has a

high mineral content (borax, salt, alkali, and lime). Material in

contact with this soil wears out quickly, and water in these areas

is extremely hard and undrinkable. Wetting your uniform in such

water to cool off may cause a skin rash. The Great Salt Lake area

in Utah is an example of this type of mineral-laden water and

soil. There is little or no plant life; therefore, shelter is hard to

find. Avoid these areas if possible.

SANDSTORMS

13-21. Sandstorms (sand-laden winds) occur frequently in most

deserts. The Seistan desert wind in Iran and Afghanistan blows

constantly for up to

120 days. Within Saudi Arabia, winds

typically range from 3.2 to 4.8 kilometers per hour (kph) (2 to 3

miles per hour [mph]) and can reach 112 to 128 kph (67 to 77

mph) in early afternoon. Expect major sandstorms and dust

storms at least once a week.

13-22. The greatest danger is getting lost in a swirling wall of

sand. Wear goggles and cover your mouth and nose with cloth. If

natural shelter is unavailable, mark your direction of travel, lie

down, and sit out the storm.

13-23. Dust and wind-blown sand interfere with radio

transmissions. Therefore, be ready to use other means for

signaling, such as pyrotechnics, signal mirrors, or marker panels,

if available.

MIRAGES

13-24. Mirages are optical phenomena caused by the refraction of

light through heated air rising from a sandy or stony surface.

They occur in the interior of the desert about 10 kilometers (6

miles) from the coast. They make objects that are 1.5 kilometers

(1 mile) or more away appear to move.

13-6

13-25. This mirage effect makes it difficult for you to identify an

object from a distance. It also blurs distant range contours so

much that you feel surrounded by a sheet of water from which

elevations stand out as “islands.”

13-26. The mirage effect makes it hard for a person to identify

targets, estimate range, and see objects clearly. However, if you

can get to high ground (3 meters [10 feet] or more above the

desert floor), you can get above the superheated air close to the

ground and overcome the mirage effect. Mirages make land

navigation difficult because they obscure natural features. You

can survey the area at dawn, dusk, or by moonlight when there is

little likelihood of mirage.

13-27. Light levels in desert areas are more intense than in other

geographic areas. Moonlit nights are usually crystal clear, winds

die down, haze and glare disappear, and visibility is excellent.

You can see lights, red flashlights, and blackout lights at great

distances. Sound carries very far.

13-28. Conversely, during nights with little moonlight, visibility

is extremely poor. Traveling is extremely hazardous. You must

avoid getting lost, falling into ravines, or stumbling into enemy

positions. Movement during such a night is practical only if you

have a compass and have spent the day resting, observing, and

memorizing the terrain, and selecting your route.

NEED FOR WATER

13-29. The subject of man and water in the desert has generated

considerable interest and confusion since the early days of World

War II when the U.S. Army was preparing to fight in North

Africa. At one time, the U.S. Army thought it could condition men

to do with less water by progressively reducing their water

supplies during training. They called it water discipline. It caused

hundreds of heat casualties.

13-30. A key factor in desert survival is understanding the

relationship between physical activity, air temperature, and

water consumption. The body requires a certain amount of water

for a certain level of activity at a certain temperature. For

example, a person performing hard work in the sun at 43 degrees

C (109 degrees F) requires 19 liters (5 gallons) of water daily.

13-7

Lack of the required amount of water causes a rapid decline in an

individual’s ability to make decisions and to perform tasks

efficiently.

13-31. Your body’s normal temperature is 36.9 degrees C (98.6

degrees F). Your body gets rid of excess heat

(cools off) by

sweating. The warmer your body becomes—whether caused by

work, exercise, or air temperature—the more you sweat. The

more you sweat, the more moisture you lose. Sweating is the

principal cause of water loss. If you stop sweating during periods

of high air temperature and heavy work or exercise, you will

quickly develop heat stroke. This is an emergency that requires

immediate medical attention.

13-32. Figure 13-2, page 13-9, shows daily water requirements for

various levels of work. Understanding how the air temperature

and your physical activity affect your water requirements allows

you to take measures to get the most from your water supply.

These measures are—

• Find shade! Get out of the sun!

• Place something between you and the hot ground.

• Limit your movements!

• Conserve your sweat. Wear your complete uniform to

include T-shirt. Roll the sleeves down, cover your head,

and protect your neck with a scarf or similar item. These

steps will protect your body from hot-blowing winds and

the direct rays of the sun. Your clothing will absorb your

sweat, keeping it against your skin so that you gain its full

cooling effect. By staying in the shade quietly, fully

clothed, not talking, keeping your mouth closed, and

breathing through your nose, your water requirement for

survival drops dramatically.

• If water is scarce, do not eat. Food requires water for

digestion; therefore, eating food will use water that you

need for cooling.

13-8

13-33. Thirst is not a reliable guide for your need for

water. A person who uses thirst as a guide will drink only two-

thirds of his daily water requirement. To prevent this “voluntary”

dehydration, use the following guide:

• At temperatures below 38 degrees C (100 degrees F), drink

0.5 liter of water every hour.

• At temperatures above 38 degrees C (100 degrees F), drink

1 liter of water every hour.

13-34. Drinking water at regular intervals helps your body

remain cool and decreases sweating. Even when your water

supply is low, sipping water constantly will keep your body cooler

and reduce water loss through sweating. Conserve your fluids by

reducing activity during the heat of day. Do not ration your

water! If you try to ration water, you stand a good chance of

becoming a heat casualty.

HEAT CASUALTIES

13-35. Your chances of becoming a heat casualty as a survivor are

great, due to injury, stress, and lack of critical items of

equipment. Following are the major types of heat casualties and

their treatment when little water and no medical help are

available.

HEAT CRAMPS

13-36. The loss of salt due to excessive sweating causes heat

cramps. Symptoms are moderate to severe muscle cramps in legs,

arms, or abdomen. These symptoms may start as a mild muscular

discomfort. You should now stop all activity, get in the shade, and

drink water. If you fail to recognize the early symptoms and

continue your physical activity, you will have severe muscle

cramps and pain. Treat as for heat exhaustion, below.

HEAT EXHAUSTION

13-37. A large loss of body water and salt causes heat exhaustion.

Symptoms are headache, mental confusion, irritability, excessive

sweating, weakness, dizziness, cramps, and pale, moist, cold

(clammy) skin. Immediately get the patient under shade. Make

him lie on a stretcher or similar item about 45 centimeters (18

inches) off the ground. Loosen his clothing. Sprinkle him with

13-10

water and fan him. Have him drink small amounts of water every

3 minutes. Ensure he stays quiet and rests.

HEAT STROKE

13-38. An extreme loss of water and salt and your body’s inability

to cool itself can cause heat stroke. The patient may die if not

cooled immediately. Symptoms are the lack of sweat, hot and dry

skin, headache, dizziness, fast pulse, nausea and vomiting, and

mental confusion leading to unconsciousness. Immediately get the

person to shade. Lay him on a stretcher or similar item about 45

centimeters (18 inches) off the ground. Loosen his clothing. Pour

water on him (it does not matter if the water is polluted or

brackish) and fan him. Massage his arms, legs, and body. If he

regains consciousness, let him drink small amounts of water

every 3 minutes.

PRECAUTIONS

13-39. In a desert survival and evasion situation, it is unlikely

that you will have a medic or medical supplies with you to treat

heat injuries. Therefore, take extra care to avoid heat injuries.

Rest during the day. Work during the cool evenings and nights.

Use the buddy system to watch for heat injury. Observe the

following guidelines:

• Make sure you tell someone where you are going and when

you will return.

• Watch for signs of heat injury. If someone complains of

tiredness or wanders away from the group, he may be a

heat casualty.

• Drink water at least once an hour.

• Get in the shade when resting; do not lie directly on the

ground.

• Do not take off your shirt and work during the day.

• Check the color of your urine. A light color means you are

drinking enough water, a dark color means you need to

drink more.

13-11

DESERT HAZARDS

13-40. There are several hazards unique to desert survival. These

include insects, snakes, thorned plants and cacti, contaminated

water, sunburn, eye irritation, and climatic stress.

13-41. Insects of almost every type abound in the desert. Man, as

a source of water and food, attracts lice, mites, wasps, and flies.

They are extremely unpleasant and may carry diseases. Old

buildings, ruins, and caves are favorite habitats of spiders,

scorpions, centipedes, lice, and mites. These areas provide

protection from the elements and also attract other wildlife.

Therefore, take extra care when staying in these areas. Wear

gloves at all times in the desert. Do not place your hands

anywhere without first looking to see what is there. Visually

inspect an area before sitting or lying down. When you get up,

shake out and inspect your boots and clothing. All desert areas

have snakes. They inhabit ruins, native villages, garbage dumps,

caves, and natural rock outcroppings that offer shade. Never go

barefoot or walk through these areas without carefully inspecting

them for snakes. Pay attention to where you place your feet and

hands. Most snakebites result from stepping on or handling

snakes. Avoid them. Once you see a snake, give it a wide berth.

13-12

Chapter 14

Tropical Survival

Most people think of the tropics as a huge and

forbidding tropical rain forest through which

every step taken must be hacked out, and where

every inch of the way is crawling with danger.

Actually, over half of the land in the tropics is

cultivated in some way.

A knowledge of field skills, the ability to

improvise, and the application of the principles of

survival will increase the prospects of survival. Do

not be afraid of being alone in the jungle; fear will

lead to panic. Panic will lead to exhaustion and

decrease your chance of survival.

Everything in the jungle thrives, including

disease germs and parasites that breed at an

alarming rate. Nature will provide water, food,

and plenty of materials to build shelters.

Indigenous peoples have lived for millennia by

hunting and gathering. However, it will take an

outsider some time to get used to the conditions

and the nonstop activity of tropical survival.

TROPICAL WEATHER

14-1. High temperatures, heavy rainfall, and oppressive humidity

characterize equatorial and subtropical regions, except at high

altitudes. At low altitudes, temperature variation is seldom less

than 10 degrees C (50 degrees F) and is often more than 35

degrees C (95 degrees F). At altitudes over 1,500 meters (4,921

feet), ice often forms at night. The rain has a cooling effect, but

when it stops, the temperature soars.

14-2. Rainfall is heavy, often with thunder and lightning. Sudden

rain beats on the tree canopy, turning trickles into raging

torrents and causing rivers to rise. Just as suddenly, the rain

14-1

stops. Violent storms may occur, usually toward the end of the

summer months.

14-3. Hurricanes, cyclones, and typhoons develop over the sea

and rush inland, causing tidal waves and devastation ashore. In

choosing campsites, make sure you are above any potential

flooding. Prevailing winds vary between winter and summer. The

dry season has rain once a day and the monsoon has continuous

rain. In Southeast Asia, winds from the Indian Ocean bring the

monsoon, but the area is dry when the wind blows from the

landmass of China.

14-4. Tropical day and night are of equal length. Darkness falls

quickly and daybreak is just as sudden.

JUNGLE TYPES

14-5. There is no standard jungle. The tropical area may be any

of the following:

• Rain forests.

• Secondary jungles.

• Semievergreen seasonal and monsoon forests.

• Scrub and thorn forests.

• Savannas.

• Saltwater swamps.

• Freshwater swamps.

TROPICAL RAIN FORESTS

14-6. The climate varies little in rain forests. You find these

forests across the equator in the Amazon and Congo basins, parts

of Indonesia, and several Pacific islands. Up to 3.5 meters (12

feet) of rain falls throughout the year. Temperatures range from

about 32 degrees C (90 degrees F) in the day to 21 degrees C (70

degrees F) at night.

14-7. There are five layers of vegetation in this jungle (Figure 14-1,

page 14-3). Where untouched by man, jungle trees rise from

buttress roots to heights of 60 meters (198 feet). Below them,

smaller trees produce a canopy so thick that little light reaches

the jungle floor. Seedlings struggle beneath them to reach light,

14-2

and masses of vines and lianas twine up to the sun. Ferns, mosses,

and herbaceous plants push through a thick carpet of leaves, and a

great variety of fungi grow on leaves and fallen tree trunks.

Figure 14.1. Five Layers of Tropical Rain Forest Vegetation

14-8. Because of the lack of light on the jungle floor, there is little

undergrowth to hamper movement, but dense growth limits

visibility to about 50 meters (165 feet). You can easily lose your

sense of direction in this jungle, and it is extremely hard for

aircraft to see you.

SECONDARY JUNGLES

14-9. Secondary jungle is very similar to rain forest. Prolific

growth, where sunlight penetrates to the jungle floor, typifies this

type of forest. Such growth happens mainly along riverbanks, on

jungle fringes, and where man has cleared rain forest. When

abandoned, tangled masses of vegetation quickly reclaim these

cultivated areas. You can often find cultivated food plants among

this vegetation.

SEMIEVERGREEN SEASONAL AND MONSOON FORESTS

14-10. The characteristics of the American and African

semievergreen seasonal forests correspond with those of the

Asian monsoon forests. The characteristics are as follows:

• Their trees fall into two stories of tree strata. Those in the

upper story range from 18 to 24 meters (60 to 79 feet);

14-3

those in the lower story range from 7 to 13 meters (23 to

43 feet).

• The diameter of the trees averages 0.5 meter (2 feet).

• Their leaves fall during a seasonal drought.

14-11. Except for the sago, nipa, and coconut palms, the same

edible plants grow in these areas as in the tropical rain forests.

14-12. You find these forests in portions of Columbia and

Venezuela and the Amazon basin in South America; in portions of

southeast coastal Kenya, Tanzania, and Mozambique in Africa; in

Northeastern India, much of Burma, Thailand, Indochina, Java,

and parts of other Indonesian islands in Asia.

TROPICAL SCRUB AND THORN FORESTS

14-13. The chief characteristics of tropical scrub and thorn forests

are as follows:

• There is a definite dry season.

• Trees are leafless during the dry season.

• The ground is bare except for a few tufted plants in

bunches; grasses are uncommon.

• Plants with thorns predominate.

• Fires occur frequently.

14-14. You find tropical scrub and thorn forests on the west coast

of Mexico, the Yucatan peninsula, Venezuela, and Brazil; on the

northwest coast and central parts of Africa; and in Turkestan and

India in Asia.

14-15. Within the tropical scrub and thorn forest areas, you will

find it hard to obtain food plants during the dry season. During

the rainy season, plants are considerably more abundant.

TROPICAL SAVANNAS

14-16. General characteristics of the savanna are that it—

• Is found within the tropical zones in South America and

Africa.

• Looks like a broad, grassy meadow, with trees spaced at

wide intervals.

14-4

• Frequently has red soil.

• Grows scattered trees that usually appear stunted and

gnarled like apple trees. Palms also occur on savannas.

14-17. You find savannas in parts of Venezuela, Brazil, and the

Guianas in South America. In Africa, you find them in the

southern Sahara

(north-central Cameroon and Gabon and

southern Sudan), Benin, Togo, most of Nigeria, northeastern

Republic of Congo, northern Uganda, western Kenya, part of

Malawi, part of Tanzania, southern Zimbabwe, Mozambique, and

western Madagascar.

SALTWATER SWAMPS

14-18. Saltwater swamps are common in coastal areas subject to

tidal flooding. Mangrove trees thrive in these swamps. Mangrove

trees can reach heights of 12 meters (39 feet). Their tangled roots

are an obstacle to movement. Visibility in this type of swamp is

poor, and movement is extremely difficult. Sometimes, streams

that you can raft form channels, but you usually must travel on

foot through this swamp.

14-19. You find saltwater swamps in West Africa, Madagascar,

Malaysia, the Pacific islands, Central and South America, and at

the mouth of the Ganges River in India. The swamps at the

mouths of the Orinoco and Amazon rivers and rivers of Guyana

consist of mud and trees that offer little shade. Tides in saltwater

swamps can vary as much as 12 meters (3 feet).

14-20. Everything in a saltwater swamp may appear hostile to

you, from leeches and insects to crocodiles and caimans. Avoid the

dangerous animals in this swamp.

14-21. Avoid this swamp altogether if you can. If there are water

channels through it, you may be able to use a raft to escape.

FRESHWATER SWAMPS

14-22. You find freshwater swamps in low-lying inland areas.

Their characteristics are masses of thorny undergrowth, reeds,

grasses, and occasional short palms that reduce visibility and

make travel difficult. There are often islands that dot these

swamps, allowing you to get out of the water. Wildlife is

abundant in these swamps.

14-5

TRAVEL THROUGH JUNGLE AREAS

14-23. With practice, movement through thick undergrowth and

jungle can be done efficiently. Always wear long sleeves to avoid

cuts and scratches.

14-24. To move easily, you must develop “jungle eye,” that is, you

should not concentrate on the pattern of bushes and trees to your

immediate front. You must focus on the jungle further out and

find natural breaks in the foliage. Look through the jungle, not at

it. Stop and stoop down occasionally to look along the jungle floor.

This action may reveal game trails that you can follow.

14-25. Stay alert and move slowly and steadily through dense

forest or jungle. Stop periodically to listen and take your bearings.

Use a machete to cut through dense vegetation, but do not cut

unnecessarily or you will quickly wear yourself out. If using a

machete, stroke upward when cutting vines to reduce noise

because sound carries long distances in the jungle. Use a stick to

part the vegetation. Using a stick will also help dislodge biting

ants, spiders, or snakes. Do not grasp at brush or vines when

climbing slopes; they may have irritating spines or sharp thorns.

14-26. Many jungle and forest animals follow game trails. These

trails wind and cross, but frequently lead to water or clearings.

Use these trails if they lead in your desired direction of travel.

14-27. In many countries, electric and telephone lines run for

miles through sparsely inhabited areas. Usually, the right-of-way

is clear enough to allow easy travel. When traveling along these

lines, be careful as you approach transformer and relay stations.

In enemy territory, they may be guarded.

14-28. Movement through jungles or dense vegetation requires

you to constantly be alert and aware of your surroundings. The

following travel tips will help you succeed:

• Pinpoint your initial location as accurately as possible to

determine a general line of travel to safety. If you do not

have a compass, use a field-expedient direction-finding

method.

• Take stock of water supplies and equipment.

14-6

• Move in one direction, but not necessarily in a straight

line. Avoid obstacles. In enemy territory, take advantage of

natural cover and concealment.

• Move smoothly through the jungle. Do not blunder through

it since you will get many cuts and scratches. Turn your

shoulders, shift your hips, bend your body, and shorten or

lengthen your stride as necessary to slide between the

undergrowth.

IMMEDIATE CONSIDERATIONS

14-29. There is less likelihood of your rescue from beneath a

dense jungle canopy than in other survival situations. You will

probably have to travel to reach safety.

14-30. If you are the victim of an aircraft crash, the most

important items to take with you from the crash site are a

machete, a compass, a first aid kit, and a parachute or other

material for use as mosquito netting and shelter.

14-31. Take shelter from tropical rain, sun, and insects. Malaria-

carrying mosquitoes and other insects are immediate dangers, so

protect yourself against bites.

14-32. Do not leave the crash area without carefully blazing or

marking your route. Use your compass. Know what direction you

are taking.

14-33. In the tropics, even the smallest scratch can quickly

become dangerously infected. Promptly treat any wound, no

matter how minor.

WATER PROCUREMENT

14-34. Although water is abundant in most tropical

environments, you may have trouble finding it. If you do find

water, it may not be safe to drink. Some of the many sources are

vines, roots, palm trees, and condensation. You can sometimes

follow animals to water. Often you can get nearly clear water

from muddy streams or lakes by digging a hole in sandy soil

about 1 meter (3 feet) from the bank. Water will seep into the

hole. You must purify any water obtained in this manner.

14-7

ANIMALS—SIGNS OF WATER

14-35. Animals can often lead you to water. Most animals require

water regularly. Grazing animals, such as deer, are usually never

far from water and usually drink at dawn and dusk. Converging

game trails often lead to water. Carnivores (meat eaters) are not

reliable indicators of water. They get moisture from the animals

they eat and can go without water for long periods.

14-36. Birds can sometimes also lead you to water. Grain eaters,

such as finches and pigeons, are never far from water. They drink

at dawn and dusk. When they fly straight and low, they are

heading for water. When returning from water, they are full and

will fly from tree to tree, resting frequently. Do not rely on water

birds to lead you to water. They fly long distances without

stopping. Hawks, eagles, and other birds of prey get liquids from

their victims; you cannot use them as a water indicator.

14-37. Insects, especially bees, can be good indicators of water.

Bees seldom range more than 6 kilometers (4 miles) from their

nests or hives. They will usually have a water source in this

range. Ants need water. A column of ants marching up a tree is

going to a small reservoir of trapped water. You find such

reservoirs even in arid areas. Most flies, especially the European

mason fly, stay within 100 meters (330 feet) of water. This fly is

easily recognized by its iridescent green body.

14-38. Human tracks will usually lead to a well, bore hole, or

soak. Scrub or rocks may cover it to reduce evaporation. Replace

the cover after use.

WATER—FROM PLANTS

14-39. You will encounter many types of vegetation in a survival

situation depending upon your area. Plants such as vines, roots,

and palm trees are good sources of water.

Vines

14-40. Vines with rough bark and shoots about 5 centimeters

(2 inches) thick can be a useful source of water. You must learn

by experience which are the water-bearing vines, because not all

have drinkable water. Some may even have a poisonous sap. The

poisonous ones yield a sticky, milky sap when cut. Nonpoisonous

vines will give a clear fluid. Some vines cause a skin irritation on

14-8

contact; therefore let the liquid drip into your mouth, rather than

put your mouth to the vine. Preferably, use some type of

container. Use the procedure described in Chapter 6 to obtain

water from a vine.

Roots

14-41. In Australia, the water tree, desert oak, and bloodwood

have roots near the surface. Pry these roots out of the ground and

cut them into 30-centimeter (1-foot) lengths. Remove the bark and

suck out the moisture, or shave the root to a pulp and squeeze it

over your mouth.

Palm Trees

14-42. The buri, coconut, and nipa palms all contain a sugary

fluid that is very good to drink. To obtain the liquid, bend a

flowering stalk of one of these palms downward, and cut off its

tip. If you cut a thin slice off the stalk every 12 hours, the flow

will renew, making it possible to collect up to a liter per day. Nipa

palm shoots grow from the base, so that you can work at ground

level. On grown trees of other species, you may have to climb

them to reach a flowering stalk. Milk from coconuts has a large

water content, but may contain a strong laxative in ripe nuts.

Drinking too much of this milk may cause you to lose more fluid

than you drink.

WATER—FROM CONDENSATION

14-43. Often it requires too much effort to dig for roots containing

water. It may be easier to let a plant produce water for you in the

form of condensation. Tying a clear plastic bag around a green

leafy branch will cause water in the leaves to evaporate and

condense in the bag. Placing cut vegetation in a plastic bag will

also produce condensation. This is a solar still (Chapter 6).

FOOD

14-44. Food is usually abundant in a tropical survival situation.

To obtain animal food, use the procedures outlined in Chapter 8.

14-45. In addition to animal food, you will have to supplement

your diet with edible plants. The best places to forage are the

14-9

banks of streams and rivers. Wherever the sun penetrates the

jungle, there will be a mass of vegetation, but riverbanks may be

the most accessible areas.

14-46. If you are weak, do not expend energy climbing or felling a

tree for food. There are more easily obtained sources of food

nearer the ground. Do not pick more food than you need. Food

spoils rapidly in tropical conditions. Leave food on the growing

plant until you need it, and eat it fresh.

14-47. There are an almost unlimited number of edible plants

from which to choose. Unless you can positively identify these

plants, it may be safer at first to begin with palms, bamboos, and

common fruits. Appendix B provides detailed descriptions and

photographs of some of the most common food plants located in a

tropical zone.

POISONOUS PLANTS

14-48. The proportion of poisonous plants in tropical regions is no

greater than in any other area of the world. However, it may

appear that most plants in the tropics are poisonous because of

the great density of plant growth in some tropical areas

(Appendix C).

14-10

Chapter 15

Cold Weather Survival

One of the most difficult survival situations is a

cold weather scenario. Remember, cold weather is

an adversary that can be as dangerous as an

enemy soldier. Every time you venture into the

cold, you are pitting yourself against the

elements. With a little knowledge of the

environment, proper plans, and appropriate

equipment, you can overcome the elements. As

you remove one or more of these factors, survival

becomes increasingly difficult. Remember, winter

weather is highly variable. Prepare yourself to

adapt to blizzard conditions even during sunny

and clear weather.

Cold is a far greater threat to survival than it

appears. It decreases your ability to think and

weakens your will to do anything except to get

warm. Cold is an insidious enemy; as it numbs the

mind and body, it subdues the will to survive.

Cold makes it very easy to forget your ultimate

goal—to survive.

COLD REGIONS AND LOCATIONS

15-1. Cold regions include arctic and subarctic areas and areas

immediately adjoining them. You can classify about 48 percent of

the Northern Hemisphere’s total landmass as a cold region due to

the influence and extent of air temperatures. Ocean currents

affect cold weather and cause large areas normally included in

the temperate zone to fall within the cold regions during winter

periods. Elevation also has a marked effect on defining cold

regions.

15-2. Within the cold weather regions, you may face two types of

cold weather environments—wet or dry. Knowing in which

15-1

environment your area of operations falls will affect planning and

execution of a cold weather operation.

WET COLD WEATHER ENVIRONMENTS

15-3. Wet cold weather conditions exist when the average

temperature in a 24-hour period is -10 degrees C (14 degrees F) or

above. Characteristics of this condition are freezing during the

colder night hours and thawing during the day. Although the

temperatures are warmer during this condition, the terrain is

usually very sloppy due to slush and mud. You must concentrate

on protecting yourself from the wet ground and from freezing rain

or wet snow.

DRY COLD WEATHER ENVIRONMENTS

15-4. Dry cold weather conditions exist when the average

temperature in a 24-hour period remains below -10 degrees C (14

degrees F). Even though the temperatures in this condition are

much lower than normal, you do not have to contend with the

freezing and thawing. In these conditions, you need more layers

of inner clothing to protect you from temperatures as low as

-60 degrees C (-76 degrees F). Extremely hazardous conditions

exist when wind and low temperature combine.

WINDCHILL

15-5. Windchill increases the hazards in cold regions. Windchill is

the effect of moving air on exposed flesh. For instance, with a

27.8-kph (15-knot) wind and a temperature of -10 degrees C (14

degrees F), the equivalent windchill temperature is -23 degrees C

(-9 degrees F). Figure 15-1, page 15-3, gives the windchill factors

for various temperatures and wind speeds.

15-6. Remember, even when there is no wind, you will create the

equivalent wind by skiing, running, being towed on skis behind a

vehicle, or working around aircraft that produce windblasts.

15-2

BASIC PRINCIPLES OF

COLD WEATHER SURVIVAL

15-7. It is more difficult for you to satisfy your basic water, food,

and shelter needs in a cold environment than in a warm

environment. Even if you have the basic requirements, you must

also have adequate protective clothing and the will to survive.

The will to survive is as important as the basic needs. There have

been incidents when trained and well-equipped individuals have

not survived cold weather situations because they lacked the

will to live. Conversely, this will has sustained individuals less

well-trained and equipped.

15-8. There are many different items of cold weather equipment

and clothing issued by the U.S. Army today. Specialized units

may have access to newer, lightweight gear such as polypropylene

underwear, Gore-Tex outerwear and boots, and other special

equipment. However, the older gear will keep you warm as long

as you apply a few cold weather principles. If the newer types of

clothing are available, use them. If not, then your clothing should

be entirely wool, with the possible exception of a windbreaker.

15-9. You must not only have enough clothing to protect you from

the cold, you must also know how to maximize the warmth you

get from it. For example, always keep your head covered. You can

lose 40 to 45 percent of body heat from an unprotected head and

even more from the unprotected neck, wrist, and ankles. These

areas of the body are good radiators of heat and have very little

insulating fat. The brain is very susceptible to cold and can stand

the least amount of cooling. Because there is much blood

circulation in the head, most of which is on the surface, you can

lose heat quickly if you do not cover your head.

15-10. There are four basic principles to follow to keep warm. An

easy way to remember these basic principles is to use the word

COLDER as follows:

• C-Keep clothing clean. This principle is always important

for sanitation and comfort. In winter, it is also important

from the standpoint of warmth. Clothes matted with dirt

and grease lose much of their insulation value. Heat can

escape more easily from the body through the clothing’s

crushed or filled up air pockets.

15-4

•

O-Avoid overheating. When you get too hot, you sweat and

your clothing absorbs the moisture. This affects your

warmth in two ways: dampness decreases the insulation

quality of clothing, and as sweat evaporates, your body

cools. Adjust your clothing so that you do not sweat. Do

this by partially opening your parka or jacket, by removing

an inner layer of clothing, by removing heavy outer

mittens, or by throwing back your parka hood or changing

to lighter headgear. The head and hands act as efficient

heat dissipaters when overheated.

•

L-Wear your clothing loose and in layers. Wearing tight

clothing and footgear restricts blood circulation and invites

cold injury. It also decreases the volume of air trapped

between the layers, reducing its insulating value. Several

layers of lightweight clothing are better than one equally

thick layer of clothing, because the layers have dead

airspace between them. The dead airspace provides extra

insulation. Also, layers of clothing allow you to take off or

add clothing layers to prevent excessive sweating or to

increase warmth.

•

D-Keep clothing dry. In cold temperatures, your inner

layers of clothing can become wet from sweat and your

outer layer, if not water repellent, can become wet from

snow and frost melted by body heat. Wear water repellent

outer clothing, if available. It will shed most of the water

collected from melting snow and frost. Before entering a

heated shelter, brush off the snow and frost. Despite the

precautions you take, there will be times when you cannot

keep from getting wet. At such times, drying your clothing

may become a major problem. On the march, hang your

damp mittens and socks on your rucksack. Sometimes in

freezing temperatures, the wind and sun will dry this

clothing. You can also place damp socks or mittens,

unfolded, near your body so that your body heat can dry

them. In a campsite, hang damp clothing inside the shelter

near the top, using drying lines or improvised racks. You

may even be able to dry each item by holding it before an

open fire. Dry leather items slowly. If no other means are

available for drying your boots, put them between your

15-5

sleeping bag shell and liner. Your body heat will help to

dry the leather.

• E-Examine your uniform for worn areas, tears, and

cleanliness.

• R-Repair your uniform early before tears and holes

become too large to patch. Improvised sewing kits can be

made from bones, plant fibers, 550 cord, and large thorns.

15-11. A heavy, down-lined sleeping bag is a valuable piece of

survival gear in cold weather. Ensure the down remains dry. If

wet, it loses a lot of its insulation value. If you do not have a

sleeping bag, you can make one out of parachute cloth or similar

material and natural dry material, such as leaves, pine needles, or

moss. Place the dry material between two layers of the material.

15-12. Other important survival items are a knife; waterproof

matches in a waterproof container, preferably one with a flint

attached; a durable compass; map; watch; waterproof ground

cloth and cover; flashlight; binoculars; dark glasses; fatty

emergency foods; food gathering gear; and signaling items.

15-13. Remember, a cold weather environment can be very harsh.

Give a good deal of thought to selecting the right equipment for

survival in the cold. If unsure of an item you have never used,

test it in an “overnight backyard” environment before venturing

further. Once you have selected items that are essential for your

survival, do not lose them after you enter a cold weather

environment.

HYGIENE

15-14. Although washing yourself may be impractical and

uncomfortable in a cold environment, you must do so. Washing

helps prevent skin rashes that can develop into more serious

problems.

15-15. In some situations, you may be able to take a snow bath.

Take a handful of snow and wash your body where sweat and

moisture accumulate, such as under the arms and between the

legs, and then wipe yourself dry. If possible, wash your feet daily

and put on clean, dry socks. Change your underwear at least

15-6

twice a week. If you are unable to wash your underwear, take it

off, shake it, and let it air out for an hour or two.

15-16. If you are using a previously used shelter, check your body

and clothing for lice each night. If your clothing has become

infested, use insecticide powder if you have any. Otherwise, hang

your clothes in the cold, then beat and brush them. This will help

get rid of the lice, but not the eggs.

15-17. If you shave, try to do so before going to bed. This will give

your skin a chance to recover before exposing it to the elements.

MEDICAL ASPECTS

15-18. When you are healthy, your inner core temperature (torso

temperature) remains almost constant at 37 degrees C (98.6

degrees F). Since your limbs and head have less protective body

tissue than your torso, their temperatures vary and may not

reach core temperature.

15-19. Your body has a control system that lets it react to

temperature extremes to maintain a temperature balance. There

are three main factors that affect this temperature balance—heat

production, heat loss, and evaporation. The difference between

the body’s core temperature and the environment’s temperature

governs the heat production rate. Your body can get rid of heat

better than it can produce it. Sweating helps to control the heat

balance. Maximum sweating will get rid of heat about as fast as

maximum exertion produces it.

15-20. Shivering causes the body to produce heat. It also causes

fatigue that, in turn, leads to a drop in body temperature. Air

movement around your body affects heat loss. It has been noted

that a naked man exposed to still air at or about 0 degrees C (32

degrees F) can maintain a heat balance if he shivers as hard as he

can. However, he can’t shiver forever.

15-21. It has also been noted that a man at rest wearing the

maximum arctic clothing in a cold environment can keep his

internal heat balance during temperatures well below freezing.

However, to withstand really cold conditions for any length of

time, he will have to become active or shiver.

COLD INJURIES

15-7

15-22. The best way to deal with injuries and sicknesses is to take

measures to prevent them from happening in the first place.

Treat any injury or sickness that occurs as soon as possible to

prevent it from worsening.

15-23. The knowledge of signs and symptoms and the use of the

buddy system are critical in maintaining health. The following

paragraphs explain some cold injuries that can occur.

HYPOTHERMIA

15-24. Hypothermia is the lowering of the body temperature at a

rate faster than the body can produce heat. Causes of

hypothermia may be general exposure or the sudden wetting of

the body by falling into a lake or spraying with fuel or other

liquids.

15-25. The initial symptom is shivering. This shivering may

progress to the point that it is uncontrollable and interferes with

an individual’s ability to care for himself. This begins when the

body’s core temperature falls to about 35.5 degrees C (96 degrees

F). When the core temperature reaches 35 to 32 degrees C (95 to

90 degrees F), sluggish thinking, irrational reasoning, and a false

feeling of warmth may occur. Core temperatures of 32 to 30

degrees C (90 to 86 degrees F) and below result in muscle rigidity,

unconsciousness, and barely detectable signs of life. If the victim’s

core temperature falls below 25 degrees C (77 degrees F), death is

almost certain.

15-26. To treat hypothermia, rewarm the entire body. If there are

means available, rewarm the person by first immersing the trunk

area only in warm water of 37.7 to 43.3 degrees C (100 to 110

degrees F).

CAUTION

Rewarming the total body in a warm water bath should

be done only in a hospital environment because of the

increased risk of cardiac arrest and rewarming shock.

15-27. One of the quickest ways to get heat to the inner core is to

give warm water enemas. However, such an action may not be

15-8

possible in a survival situation. Another method is to wrap the

victim in a warmed sleeping bag with another person who is

already warm; both should be naked.

CAUTION

The individual placed in the sleeping bag with the victim

could also become a hypothermia victim if left in the bag

too long.

15-28. If the person is conscious, give him hot, sweetened fluids.

Honey or dextrose are best, but if they are unavailable, sugar,

cocoa, or a similar soluble sweetener may be used.

CAUTION

Do not force an unconscious person to drink.

15-29. There are two dangers in treating hypothermia—

rewarming too rapidly and “after-drop.” Rewarming too rapidly

can cause the victim to have circulatory problems, resulting in

heart failure. After-drop is the sharp body core temperature drop

that occurs when taking the victim from the warm water. Its

probable cause is the return of previously stagnant limb blood to

the core (inner torso) area as recirculation occurs. Concentrating

on warming the core area and stimulating peripheral circulation

will lessen the effects of after-drop. Immersing the torso in a

warm bath, if possible, is the best treatment.

FROSTBITE

15-30. This injury is the result of frozen tissues. Light frostbite

involves only the skin that takes on a dull whitish pallor. Deep

frostbite extends to a depth below the skin. The tissues become

solid and immovable. Your feet, hands, and exposed facial areas

are particularly vulnerable to frostbite.

15-31. The best frostbite prevention, when you are with others, is

to use the buddy system. Check your buddy’s face often and make

15-9

sure that he checks yours. If you are alone, periodically cover your

nose and lower part of your face with your mittened hand.

15-32. The following pointers will aid you in keeping warm and

preventing frostbite when it is extremely cold or when you have

less than adequate clothing:

• Face. Maintain circulation by “making faces.” Warm with

your hands.

• Ears. Wiggle and move your ears. Warm with your

hands.

• Hands. Move your hands inside your gloves. Warm by

placing your hands close to your body.

• Feet. Move your feet and wiggle your toes inside your

boots.

15-33. A loss of feeling in your hands and feet is a sign of

frostbite. If you have lost feeling for only a short time, the

frostbite is probably light. Otherwise, assume the frostbite is

deep. To rewarm a light frostbite, use your hands or mittens to

warm your face and ears. Place your hands under your armpits.

Place your feet next to your buddy’s stomach. A deep frostbite

injury, if thawed and refrozen, will cause more damage than a

nonmedically trained person can handle. Figure 15-2, lists some

“dos and don’ts” regarding frostbite.

Don’t

• Periodically check for frostbite.

• Rub injury with snow.

• Rewarm light frostbite.

• Drink alcoholic beverages.

• Keep injuried areas from

• Smoke.

refreezing.

• Try to thaw out a deep frostbite

injury if you are away from

definitive medical care.

Figure 15-2. Frostbite Dos and Don’ts

TRENCH FOOT AND IMMERSION FOOT

15-34. These conditions result from many hours or days of

exposure to wet or damp conditions at a temperature just above

15-10

freezing. The symptoms are a sensation of pins and needles,

tingling, numbness, and then pain. The skin will initially appear

wet, soggy, white, and shriveled. As it progresses and damage

appears, the skin will take on a red and then a bluish or black

discoloration. The feet become cold, swollen, and have a waxy

appearance. Walking becomes difficult and the feet feel heavy and

numb. The nerves and muscles sustain the main damage, but

gangrene can occur. In extreme cases, the flesh dies and it may

become necessary to have the foot or leg amputated. The best

prevention is to keep your feet dry. Carry extra socks with you in

a waterproof packet. You can dry wet socks against your torso

(back or chest). Wash your feet and put on dry socks daily.

DEHYDRATION

15-35. When bundled up in many layers of clothing during cold

weather, you may be unaware that you are losing body moisture.

Your heavy clothing absorbs the moisture that evaporates in the

air. You must drink water to replace this loss of fluid. Your need

for water is as great in a cold environment as it is in a warm

environment (Chapter 13). One way to tell if you are becoming

dehydrated is to check the color of your urine on snow. If your

urine makes the snow dark yellow, you are becoming dehydrated

and need to replace body fluids. If it makes the snow light yellow

to no color, your body fluids have a more normal balance.

COLD DIURESIS

15-36. Exposure to cold increases urine output. It also decreases

body fluids that you must replace.

SUNBURN

15-37. Exposed skin can become sunburned even when the air

temperature is below freezing. The sun’s rays reflect at all angles

from snow, ice, and water, hitting sensitive areas of skin—lips,

nostrils, and eyelids. Exposure to the sun results in sunburn more

quickly at high altitudes than at low altitudes. Apply sunburn

cream or lip salve to your face when in the sun.

SNOW BLINDNESS

15-38. The reflection of the sun’s ultraviolet rays off a snow-

covered area causes this condition. The symptoms of snow

15-11

FM 3-05.70 Field Manual Survival (17 May 2002) - page 8