Here's what I would do:
Find a nice, straight Elm or White Ash, about 4 inches in diameter, and that has a nice section in it 6-7 feet long if you are looking to build an ELB (English long bow). Try to split it so that both haves come out straight left to right. Seal both ends with wood glue, or some other kind of sealant, and set them in a warm DRY spot to season at least a couple weeks, or longer if you can hold out. What do you drive? If you could set them in your vehicle, that's a nice way to dry them out. But be sure to seal the ends, because trying to dry them faster than natural can cause them to split.
Let me say it like this. You could put some effort into it and have a sappling stave cut and dry in a week or two. But to me, seasoning wood is as much abouit time as it is humidity; others would surely disagree. But if you cut a 4 inch sappling, split it like I said, seal both ends of each half, you should be able to dry it out enough in a couple weeks using White Ash or Elm.
~~Papa Matt