Just because it has wide rings doesn't mean its not erc...that's def juniperus virginiana...I find the wider ringed stuff to be more "pale" in color...and not as dense...lots you can do with that stave...i see two options and I either case I'd get it down as close to one growth ring(chase a ring),and then drill n plug those knots,and then from there you can either shorten it up and make a sinew backed bow,or a longbow at around the length it already is with a good rawhide backing....either of those would be best for your current skill level....could you plane it flat n glue a hickory or bamboo backer on...sure ya could...but I'd stick with simple now for you...BUT its up to you,not me n what I think...just my two cents.....by the way I've done all the above and sinew is my favorite backer for erc....