To get a fire going, you’re going to need something to catch a flame. That is your tinder. There are many things you can bring along with you, however, nature is pretty good at providing some options, the best, in mine, and a lot of others’ is Paper Birch tree bark, no matter the conditions. It burns at a high temperature as well.
What you see in the photo above is the Paper Birch tree (a/k/a White Birch or Canoe Birch). The bark just pulls right off, and if you find one that is down, can come off in very large sheets. This stuff burns like the dickens.
Birch can be found in Canada and the Northern US, as shown in the range map from Wikipedia (click to go to the original image and size).
If you are backpacking in these areas, and you are going to have a fire, as you hike along the trail, pick some of this up here and there, especially from felled trees, and strap it to your pack. From my backpacking trip last fall, it rained the entire time, and Paper Birch got the fire going, and kept it going, when all we could muster up was some damp and wet wood.
It is a natural resource, but, like all resources, must be moderated in use. Practice Leave No Trace principles when in the out-of-doors. If you do not need a fire, do not have one.
More information on the birch can be found in this USDA plant guide here.
Survival Tip: While not highly nutritious, the sap and inner bark of the paper birch tree is edible.