Can I put authentic wood from the country wilderness in my grill?

We don't have charcoal, so could I go find dry wood from the outside trees? How would I properly go about doing all that? That's how the cavemen did it right?Can I put authentic wood from the country wilderness in my grill?
As long as you don't use pine. Too much resin. Any hardwood should do nicely. Stay away from elm also. It just doesn't burn well. Birch makes a nice fire and is easy to light.
You can cook with it. If you know what kind of wood it is you can use it to smoke your dinner. Be careful, you don't want to accidently use pine. You can also burn the wood down to coals and cook over that. However this could be damaging on your grill.Can I put authentic wood from the country wilderness in my grill?
You want to cook your food over wood that has had animals "mark their scent" on it or other chemicals, mold or moss, etc... on it? I have other plans for dinner!