That looks like grape vine with the bark removed to me. I could be wrong but I'm pretty sure. If it is your going to have to boil it like crazy. I bought some before and actually gave up on it because of the tannins. The only thing I can suggest is getting a big tub or something and put the wood in it. Then a ridiculous amount of trips from the stove with boiling water and your done. You might want to try a large rigid plastic storage container. ~$15 bucks from lowes or home depot.
Just my 2 cents....
Just my 2 cents....
