From the Knit Rowan website:
Knit this garter stitch scarf, which is now available as a download exclusive. Designed by Sarah Hazell in Fazed Tweed it cleverly uses weaved in yarn after knitting to create a plaid effect.

Now available for $7 as an individual download in English at our Ravelry Store

Finished dimensions:
Completed scarf measures 22 cm (8½ inches) wide and 195 cm (77 inches) long.

Yarn information:
Rowan Fazed Tweed
A - Larch 002
3 skeins
228 yards

B - Elm 008
3 skeins
228 yards

C - Yew 004
3 skeins
228 yards

D - Bay 006
1 skein
76 yards

E - Elderberry 011
1 skein
76 yards

F - Holly 007
1 skein
76 yards

G - Maple 001
1 skein
76 yards