This is part of the fun of being in the wilderness....just experiment and try things. Several have gotten you started on your journey so now go out and try, try, and try. You will learn much more from your failures than you will your successes.
Keep in mind basically, anything that once was alive or part of a living organism and now is dead 'n dry is going to burn. I.e. dung from whatever, grasses, leaves, bark, wood shavings (beside fat wood), fluff from plants, decomposed wood fiber and the list goes on and on. Keep in mind the smaller and shorter duration of the heat base vis 'a vis the initial flame/spark then the finer and thinner the tender. This is why a spark from a ferro rod isn't effective on fat wood until it is reduced into fine dust (the smallest sawdust size). Grass is great as an initial tinder as long as you break down the fibers and rough it up so a tiny hair from the inner fiber can catch a spark (assuming you're using a spark based fire starter). Learn how to build tinder bundles, then interlace the bundle with various materials and observe what catches quickly but doesn't last, and what is more difficult to catch a spark but sustains the flame into a fire.
