I had some left over pine 1x8 8ft long boards, so I decided to use them for our garden beds. The wood isn't pressure treated, and the boards aren't really very sturdy, so I don't really expect them to last more than a couple of seasons. As you can see in the above picture, I used 3 boards to make each bed. One 1x8 was cut in half to make the ends, and the other 8ft boards comprise the sides. I cut some 6 inch long pieces of 2x4 for backing in the corners where the boards are screwed together. I did'nt want to use pressure treated lumber, because I'm afraid the chemical treatment of the boards, could leach into the soil and eventully contaminate our plants. This may not be a real danger, but I'd rather be safe than poisoned. I had recently brought in a load of top soil to fill some holes in the yard, so I used a bit to fill the bottom 2 inches of the beds. The quality of the top soils was pretty bad (mostly sand and small mulch shavings) so I filled the beds the rest of the way with some good compost from the pile in the background of the picture above.