I use an arborist's line, Zing It. It's very light, strong, and doesn't stretch. It also is kinder than other ropes/cords to tree bark. But most often I just take a bear canister where there are actually bears - the line/bag I only ever use on the coast, where the raccoons are the real issue.
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"In the beginner's mind there are many possibilities. In the expert's mind there are few." Shunryu Suzuki

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