Everyone knows the easy way to age a tree—cut it down and count the growth rings. The trouble is there’s an obvious flaw in this method: it kills the tree.
Fortunately there are several other ways to age a tree without resorting to this terminal solution. Here are four of them.
CORE EXTRACTION
You can use a specialized drilling tool to count tree rings without damaging the tree. An increment borer is a special drill consisting of a handle, a drilling bit, and a small core extractor that fits into the auger bit. Drill into the tree at chest height using a borer the length of which is at least 75 percent of the tree’s diameter. Put your body weight into the first few turns to get it going, making sure to keep the drill horizontal.
Keep turning the handle until the end of the well-lubricated drill reaches just a little farther than half way (i.e., just past the pith—the tree center). While the tool is still in the tree, carefully introduce the core extractor through the back of the drill. Make sure the open side of the extractor is facing downward. Then make one-half turn of the drill in the reverse direction and then slowly withdraw the core extractor. Now count the rings. Most trees produce two rings each year: one light spring ring and a darker summer ring. You can count either to determine the age of the tree. Add on a few years to allow for the early growth that won’t show up in your sample.
COUNT THE WHORLS
Each year a new whorl is created when a bud bursts through the tip of the tree to form a new branch. In some species counting tree whorls (spiral scars on the trunk) can give a rough estimate of the age. Count the number of whorls above chest height and add one year.
COUNT THE GAPS
Count the number of gaps between branch sections, including the section at breast height, and above the last branch.
MEASURE THE CIRCUMFERENCE
Measure the circumference of the trunk about 5 ft (1.5 m) above the ground. Calculate the radius (distance from center of the tree to its outer edge) using the formula r = C/2Π (i.e., divide the circumference by 6.283). Then divide the radius by the average yearly tree growth for your tree species (available online) to find its age.
COLLECT, FILTER, AND PURIFY WATER
Collecting water and making it safe to drink is one of the most important survival skills.
A human being can survive for several weeks without food, but barely three days without water. One of the best ways to collect water (without relying on the rain) is to construct an evaporation trap.
HOW TO MAKE AN EVAPORATION TRAP
You will need some plastic sheeting, a digging tool, a 1¾-pint (1-liter) container, a drinking tube (optional), and some rocks.
• First find a moist area that receives sunlight for most of the day. Dig a bowl-shaped hole about 3 ft 3 in (1 m) in diameter and about 2 ft (60 cm) deep.
• Dig a hole the width of your container in the middle of the floor of the hole and sink the container into it.
• If you have a drinking tube, place one end in the container and the other end outside the hole.
• Place the plastic sheeting over the hole, trap the edges with rocks and then place a single rock in the center of the sheeting so that it forms an inverted cone. Then seal the edges of the sheeting with soil so air cannot escape from the hole.
During the day, the heat of the sun will make the moisture in the ground evaporate into the air, but it will condense again when it hits the plastic sheeting, and this condensed water will drip down the inside of the sheeting and collect in the container. A large trap should produce about 1¾ pints (1 liter) of clean water a day.
HOW TO FILTER WATER
Fill a container (hollow log, plastic bag) with alternating layers of rock, sand, and cloth. Make about ten small holes in the bottom of the container and place an empty container underneath. Then pour water into the top of the filter. This process will remove grit and sediment (a filter made solely of cloth will only remove visible particles). If possible, allow the water to sit for twelve hours after being filtered, to improve the taste.
HOW TO PURIFY WATER
The best way to purify water is to boil it for at least ten minutes. Alternatively, let the water sit for at least six to eight hours in full sunlight. The ultraviolet light will kill most microorganisms.
MAKE A DUGOUT CANOE
If you can only spare a couple of days, use a chainsaw, but if you have a month to burn, why not try the traditional Native American method of using fire as the main tool to hollow out your canoe?
1. Locate and chop down a pine tree with a trunk base that is completely straight, at least 20 ft (6 m) long and about 3 ft (90 cm) in diameter (you can also use a hardwood such as elm or chestnut). Traditionally you would chop down a tree close to a river and work it into a canoe on the river bank, because there would be no easy way to transport the log somewhere else.
2. Strip the branches and place the trunk on a row of smaller logs so that it can be maneuvered more easily.
3. Remove the bark using a three-quarters ax, spade, or a foot adze.
4. Flatten the top by sawing or chopping parallel lines across the trunk and then chipping away with an ax or adze.
5. Dig a depression under the front and back ends of the log and light a fire in each. The flames will burn the underside of the log so you can chop away the charred wood with an adze to create a sloped bow and stern.
6. Burn fires on top of the log along its length and dig out the charcoal each day to hollow out the inside of the canoe. This will take several days. Protect the sides and other areas that you don’t want to burn by splashing them with water or backfilling them with clay and mud.
7. Don’t let the fire go out. Keep tending it round the clock and make sure you aren’t burning the precious sides. The sides should be about 2 in (5 cm) thick.
8. Once you have created the rough interior, lay smaller targeted fires to burn away areas that are too thick, using rocks to press the fires against the targeted areas, while protecting the areas that are already at the required thickness.
9. Traditionally, clam shells would also be used to create a smooth finish inside and out. Then the wood would be rubbed with animal fat.
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