As you messaged me asking to take a look, I shall tell you what I think!
As Pearl said, you're in for a pretty tough challenge. I'm not sure how many bows you've made before, but even if you're pretty experienced, you're using a wood most bowyers would avoid. That's not to say that it can't be done with something like pine or spruce, but you need to make sure you alter any design you're working from to suit the wood.
Either make it MUCH wider than you would with a normal hardwood, or much longer. Thimo made a 7ft pine longbow with a very rectangular cross-section over on PP a while ago, but even with his expertise and experience the bow started taking quite a lot of set and had very little cast. What style of bow are you hoping to make?
This will obviously be a great learning curve for you, but it may not produce much in terms of efficient, quick bows. Just dealing with those knots will teach you a huge amount. I'd use these logs as practice for laying out a bow within a stave, splitting in the right place, getting experience with drawknifes and rasps and perhaps even learn how to heat-treat, flip tips or even billet as you haven't got anything to lose. Once you've picked up a few lessons through doing, get yourself a proper bow wood and you should be off to a flying start!
Best thing I can possibly suggest is to make sure the bow design suits the wood. You definitely won't get a classic English longbow out of this wood, and you'll struggle to get a traditional flatbow profile either, so you'll have to alter and adjust designs to suit wood like this. I hope that's correct, and I'm sure more experienced bowyers than me will be able to correct me if I'm wrong. You might need to trap the back as well, so read up on that.
