Hidasuki (緋襷) is a style of Japanese Bizen pottery. As far as I can tell the pots are unglazed and wrapped in rice straw before firing. The straw leaves distinctive red lines on the clay. For my experiments I used white stoneware clay fired in a saggar. The original method calls for rice straw which is hard to get here. Also some resources claim that the straw is soaked in salt water prior to wrapping the pots. Some potters seem to use sea weeds instead of rice straw. Since this is my first try and it’s hard to find information I used the tips of dried bamboo. The white stoneware clay was fired to about 1200°C. The pots certainly turned into a beautiful toasty color. Unfortunately there are only a few very slights marks from the bamboo.
One problem with the bamboo is that it’s hard to wrap around the pots tightly. I suspect that you need to have very good contact to the pots. It probably depends a lot on the type of clay and the amount of wrapping. The more straw you put into the saggar the more it will influence the atmosphere during firing. I fired pots in a saggar full of charcoal before. That turned the pots completely black.
I will do further tests in my next firings and post the results. One of my two saggars broke so I will probably need to make a new one.