The stitch is found in many different patterns with many different names. Basically it is called a "Crazy Stitch" or a "Box Stitch" ... where you chain three, double crochet three, sc to the fabric across the row. On the way back you then chain three at the top corner of the first pass across and then do the 3 dc inside the chain three. I think if you click on the photo it will come up in a larger view and you will be able to see the pattern emerge on the while stitches. I didn't use a pattern for this...just made it with yarn left over from my brother's afghan using the same stitch all the way through.
2 days ago