It is extremely difficult to see people on the ground from the air. Even some wreckage is hard to see, depending on the bush or other surroundings. When Search and Rescue are looking for someone, if they dont see them in one area, they move on. So it would be a great shame if you heard them coming, and they fly over and dont see you. That is why signaling is such a priority, even before organic food, water and shelter.
This is a pretty nice video from Rob at Sigma 3 Survival school that illustrates how to fairly easily get water from a tree. This could come in handy in a survival situation but according to the narrator is only effective 2 times a year (early spring and late winter) and works better with certain trees.
Rob also demonstrates how to use a root from the tree to support your canteen while the water flows into it.
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