Montana winds have a reputation for blowing camp tarps into the next county. Usually this is because the tarps lack secure and flexible attachments or anchors.
Traditionally, the Taught Line Hitch is the go-to, adjustable knot for the job. Every Boy Scout learned this useful knot, after they tied a Square Knot. The great thing about the knot is that it is tight until you make tension adjustments. When the tent or tarp leads begin to loosen in the wind, you can quickly increase the secure tightness of the knot. ￼
You can also anchor Sail style tarps using this technique. To allow for some flexibility, consider adding springs to the anchor points. This expandable hardware will give in the wind. The Sail, or tarp, or tent lines, will give a little then tighten back up. The sails and tarps will float in the wind rather than tearing free and floating away. ￼
For those that can’t tie a proper knot, you can use metal or wooden holed sticks to secure the lines. You can buy or make them. The inline attachments use leverage to secure the tension on tent and tarp leads.
It is also important to anchor your tent and tarp stakes securely. In sandy soil, you will want to bury the stakes to anchor them. Rocky soils mean that nail like spikes may be appropriate. You can also stack a big rock in front of the stakes. Wooden supports will also add stability is harsh weather. Different tent stakes are better in different soils.
Metal grommets or reinforced attachment hardware will keep tarts and tents from tearing. Securing guidelines to trees works but be aware of how the trees are moving and swaying. Also look for any limbs or trees that could break and fall onto your camp. ￼
Allow the tarp to stay up during the rain and snow to keep you dry. Monitor and manage them as needed. That is why you put the tarp up in the first place.
Stay dry, secure, and safe!