I use the larger thicker pieces as a base, which I sit the thinner ripped up nest onto, and strike into that. Once alight, its nice and easy to lift the whole thing up and place it into the wood you've got prepped and ready to light. I find this easier than trying to lean into the wood I've prepped and arranged (usually an upside down fire) and trying to strike there. I find it much easier to be accurate with where I shower the sparks this way, as I can sit down and place it between my feet. Hugh; Its only really worth attempting to scrape the bark if you have a nice thick piece of bark. I imagine it would be very difficult to scrape a pile of dust from the bark you pictured.