Ch 3 counts as dc throughout
Ch 7 (counts as ch 4, dc)
Row 1: dc in 4th ch from hook, dc in each dc across
Row 2: ch 3, turn, dc in blo of each dc across to last 2 dc, 2dc in blo in next dc, dc in beg ch 3
Row 3: ch 3, turn, 2 dc in blo in next dc, dc in blo of each dc across, dc in beg ch 3
Rep rows 2 and 3 until you have either used just under half your yarn, or until it is half of the desired length.
Row 4: ch 3, turn, dc in blo in each dc across to last 3 dc, dc2tog in blo, dc in beg ch 3
Row 5: ch 3, turn, dc2tog in blo, dc in blo in each dc across, dc in beg ch 3
Rep rows 4 and 5 until there are 5 dc sts including the ch 3
Fasten off and weave in all ends.
I love the ridges you get from only using the back loop. The yarn is sort of smooth and shiny and it helps enhance the stitch. It's such a simple stitch, but it has a great effect. My scarf is 55" across the top and 11.5" at the widest point.