Thanks all for the article and suggestions. Since my H26 trailer is designed for the thinner boards (the brackets on the rear crossmember will accommodate just less than 1"), I will stay with a 1X8 board or the 3/4" plywood to keep the original load bearing relationship (as Crazy Dave cautions). My thought is to stay with the original plywood idea for strength and flexibility over a treated pine plank, but 1x8 planks would be a less expensive solution than buying a whole sheet of plywood to get two 8-inch wide strips. Rgranger-how are your deck planks working out? (Although in your photos they sure look like plywood!)