Bears, where do I start. Leave your tent open and maybe it will not be destroyed. Do not ever have food or scented things in your tent, cherry flavored chapstick for instance. Use an aircraft cable 1/4" to 5/16" in diameter with loops at both ends, crimped connector type loops. Use one of the ~ 1/4"small threaded closure pear shaped non-caribeener type connectors on each end. Throw a small rope attached to a rock way up into the tree branches. Pull one end of the cable upwards, just as the other end starts to lift off the ground attach a small climbing pulley to the cable via the pear shaped threaded attachment device and then thread some parachute cord through the pulley. Tie both ends of the parachute together and attach them to something to maintain control over the pulley end of the steel cable.
Once the first end of the cable comes back where you can reach it attach it with some tension on it so that the pulley is 20' or so off of the ground. To attach it wrap the steel cable around a tree and when the end with the pear shaped attachment is really close to the tree simply click it over the cable and screw the threaded unit together. You now have a steel cable that will be holding up your two food bags, sleeping bag stuff sacks or sacks for food storage with cord/rope closures, on the end of an easy to manage rope system. Always maintain control over the ends of the rope or it will fall down from the pulley and all will need to be done again. Tie a bag of food to one end of the rope, the food bags should be close to the same weight. Pull the first bag of food all the way up to the pulley (note here that the cable/rope system should not be within 5' of any tree). Stand nearly underneath the first food bag, reach up as high as you can and attach the second food bag using a slip knot as the final tie down method. Tie a ~10" diameter loop at the end of the parachute cord with a solid knot, take up the rest of the parachute cord by wrapping it loosely around the hand and elbow of one of your arms, stuff the excess cord part way into the stuff bag leaving most of the excess hanging and the tied looped end hanging down to just the bottom of the stuff bag. With a long stick push the second bag upwards, the upper bag will start coming down, stop pushing when the bottoms of both bags are about even with each other. The bags should now be about 12 feet or so from the ground itself and this will suffice for most bears standing on flat footed on the ground.
To retrive the bags take a long stick and grab the loop end of the rope and jerk on it to pull out the excess cord, pull one bag down, remove it from the slip knot, holding the rope securely slowly lower the upper bag to the ground, while holding the looped ind of the cord untie the know on the first bag, secure both ends of the cord together and tie them to something like a tree.
I put this method to use after the bears in Northern California had learned that anything that was hung up was to be attacked as it would have food in it. They can chew through parachute cord easily but the aircraft cable is a different story, I've never lost a bag of food since I began using the steel cable in this method. I've had Many bear encounters, two with a sow and her cub('s). The first was not a fun experience as she put US between Her and her Cubs, the cubs stayed in camp while she went to the food bag tree leaving us between the sow and the cubs, we were asleep. The second was not quite as dangerous but any encounter between humans and a sow with cubs can go wrong at any moment. The cubs are cute and bears can be magnificent but do not feed them or attempt to touch them! The first sow/cub incident had the sow standing in front of our tent rocking back and forth on all fours and grunting, all I had with me was a .22 revolver and my young son. Several hours after the bears left we went on a day hike and returned to a wrecked camp and our food taken, the food bag was not on a steel cable. The next day they did the same thing, wrecked the camp and hit what was left of the food bag. Oh, the second contact between sow and cub left me with a wrecked camp (I'd sinned and zipped the tent closed, they could not easily go in and inspect so they tore the tent and equipment up). Again, they had left the site and after a few hours I went for a day hike, they returned and did their thing.
Since I go backpacking frequently into this country I now carry a .454 Casull revolver. I have no desire to kill a bear but if it threatens myself or my equipment and if the roar from this cannon does not make it leave well, I've not reached that point yet as the roar has always scared them away and they stay away. The cable, the attachment links, the pulley and cord are all heavy but it keeps your food safe and therefore you safe..............63bkpkr
