Edge grain, for sure. What I did: I bought a 2" thick, 6'board, which was 8" wide, plain sawn. I turned it on edge, and ripped 3/16" thick strips on the table saw from the 2" face. Viola! 2" wide edge grain backing strips. The hickory board I found was very straight grained, with no run off. Then, I ran it through a thickness sander to true it up, making them 1/8" thick. Each strip ended up costing me $10. Not bad. No fuss, just glue it up and go.