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The clothing should be loose enough to allow full range of motion, but not baggy enough to snag on branches. Remove all loose jewelry and accessories, especially from around your neck, as these may snag during the climb. If possible, wear flexible shoes with good traction. If your shoes have hard soles or poor traction, climbing barefoot might be easier. Find a tree with large, strong branches that can support your weight, at least 6 inches (15 cm) in diameter. Before you start the climb, step back far enough to inspect the whole tree. Avoid trees with any of the following signs of danger: Strange shapes or turns in the trunk. Leaning trees are risky but sometimes safe. Deep cracks. Large areas of sunken or missing bark. A forked top is a sign of decay in conifers. Other types of tree might still be safe, but do not try to reach the fork. Approach the tree and inspect the lower trunk and the circle of ground 3 feet (0.9 meters) around it. These are all signs of a damaged or dying tree that is unsafe to climb: Mushrooms or other fungus growing on the tree or around the base. Many dead branches on the ground. (A few dead branches attached to the lower trunk is common, but if they're falling from higher up, there's a more serious problem.) A large hole or several small ones in the base. Severed roots, or a raised or cracked area of soil next to the trunk (a sign of uprooting). Even if the tree is sturdy, weather conditions could make the climb more dangerous. Understand how the following affect your climb: Never climb during a thunderstorm, or in strong wind. Wet conditions can make the tree slippery and very dangerous to climb. Cold temperatures make wood brittle. Plan on climbing slowly and testing every branch before you use it as support. There's one last safety step before you can get started. Look closely for the following dangers. These can be difficult to spot from the ground, so keep an eye out while climbing as well. Never climb if there is a power line within 10 feet (3 meters) of the tree's branches. Do not climb below large branches that have broken off and snagged in the tree. Climbers call these "widow makers" for a reason. Check the tree and nearby trees for bee and wasp colonies, or large bird or mammal nests. Avoid the trees immediately around these animals.
Wear well-fitting clothing. Examine the tree from a distance. Check near the ground. Allow for poor weather conditions. Look for local dangers.