I always planned to work Selva in the round, especially since I had not originally included a slit. Since the skirt was quite fitted, I realized this would require that it be above knee length; but after calling to tell me that Interweave wanted to use the design, Eunny Jang, the editor, told me she thought it might require both a slit and a zipper closure. This got me wondering whether I should work the skirt flat and then seam it up the back, thus easily allowing for a slit and a zipper-- but I decided against this, mainly because I thought it would be significantly slower knitting.
A bit of good news: Eunny wanted me to use Filatura di Crosa Zara, the exact same yarn I had used for the swatch (very unusual, in my experience!). Unfortunately, not expecting this, I hadn't bothered to take any notes on the gauge of the Hearts of Oak swatch I had sent to Interweave, so as soon as the yarn arrived in the mail, I swatched again. After blocking, the swatch seemed a little too loose to me, so I did another one on smaller needles, and decided to use the smaller needles for the skirt to get a slightly denser fabric (trying not to calculate how many extra stitches I would have to knit to finish the thing!).
My 2 cents on swatches: I've decided that patterns which include stitch patterns other than stockinette stitch should give gauges both in stockinette stitch, to make it easier to find substitute yarns, AND in one or more of the pattern stitches used in the design, since working cables or lace or garter stitch, or whatever, might cause changes in yarn tension among different knitters. In future all my patterns will include at least two gauges (I can't imagine myself creating a design using only stockinette!).
Back to Selva: First, I decided I didn't want to have a facing around the slit; this meant that I would have to find a way to make the edge of the knit fabric itself look finished. With no facings (meaning that working in the round and then steeking was not an option), the skirt would have to be worked back and forth for the length of the slit, and then joined to work the rest in the round. After some experimenting I came up with a modification of the Hearts of Oak pattern which looked adequately finished at the edges; I also found that having a 2-stitch stockinette edge was important, to keep the edge fairly straight. I started knitting, only to realize after several inches that I had no idea whether the Hearts of Oak pattern worked on circular needles would show a jog at the beginning of each round! At this point, I just kept my fingers crossed until the skirt was about 7 inches long, joined for working in the round, and...no jog whatsoever! In fact, I found that the increases and decreases in the stitch pattern caused the beginning of the round to move in and out along the edges of the "overlapping scales" (as described by Interweave), which is why I set up the chart for rounds (at left) the way I did.
Next and final post on Selva: waistband issues and sizing.