This time, our theme is moss. In some countries, it is regarded almost as a weed, but in Japan, it's cherished. Moss can be found in the gardens of temples and shrines, in forests and mountains and even in large cities. Our main guest is Oishi Yoshitaka, an associate professor at Fukui Prefectural University. He introduces us to different species of moss, and explains the role it plays in both the natural world, and in Japanese gardening. And in Plus One, Kanoa makes a beautiful moss terrarium.