According to the Vinaya-pitaka of the Pali Canon, one day the Buddha asked his cousin and attendant, Ananda, to sew a robe in the pattern of a rice field. Ananda did this, and the pattern has been repeated on monks' robes in most schools of Buddhism ever since.
As you can see in the inset photo, rice paddy fields can be roughly rectangular and separated by strips of dry ground for paths. The rice field pattern in the Theravada robe shown in the photo is in five columns, but sometimes there are seven or nine columns.
