12:17 p.m. on February 12, 2010 (EST)
Hey spulaski53,
I did the tarp thing for a while, still do on occasion.
I did some section hiking on the AT (Appalachian Trail) for a spell, and experimented with three different shelter systems during that period.
I tried a tarp, a hammock, and a single pole pyramid tent with no floor.
They all had their strong points and weaknesses.
Some things I learned with tarps are:
1. Picking the right spot is very important I learned, ideally I looked for a spot that was higher than the surrounding land, a high spot drains water during downpours and that can be a lifesaver. Look at the terrain around you and think about how the water is going to flow during a downpour if there is any chance of rain.
2. I looked for smallish trees to camp amongst, I tried to avoid trees with big limbs that looked like they could crack during storms. If you can pitch your tarp with just your trekking poles and guy lines / stakes, that gives you more flexibility for picking camping spots, but that's hard to do with large tarps in my experience. It just helps to have a ridge line between two trees. Having some shade also helps avoid UV damage to your tarp, and makes life better in warmer months.
3. I found that the tarp I started out with was not big enough, it just did not provide enough shelter for me and my stuff, I ended up with a 12 x 12 catenary cut tarp. If you get a tarp big enough you can stake the windward side all the way to the ground. This helps a lot during storms, and helps with those winter wind chills.
4. Consider getting a bivy sack for your sleeping bag, this will give you extra protection for keeping your bag dry from blowing rain, sleet, or snow. This was something I had to do in order to keep my bag dry during longer trips, your area may be more arid, just something to think about.
5. Keep your sleep area as free of food odor as possible. You may or may not be going in bear country, regardless I would recommend hanging ALL your smellables, (food, soap, toothpaste, chapstick, etc.) or using a bear canister at least 100' from your sleeping area. I also would recommend cooking & eating at least 100' away as well. This should cut way down on critters coming into your sleeping area, not completely, but it should make a big difference.
I still use a tarp at times, but to tell you the truth, by the time I set up all the things that I need to stay warm and dry with a tarp it's just easier for me to take a tent. A large part of that is because of where I backpack, we have a lot of thunderstorms with high wind. Your situation may be different and you may find a tarp works good for you. Everyone ends up with their own 'system' that works for them, and I've never seen two tarp set ups that were just alike.
You just got to get out there and do it some to develop your own personal system, however I would suggest that just like any other set up you try it out at home or close to your vehicle a couple times first. You don't want to spend the night cold and wet 15 miles up the trail with your tarp blown away and stuck up in a tree, and it's raining on you!
I saw that happen once.
You can get some good advise on tarp set ups here:
http://www.backpackinglight.com/cgi-bin/backpackinglight/forums/thread_display.html?forum_thread_id=1543
Happy trails!