Kama (Sickle)

The kama is an agricultural sickle and many were certainly imported from China for the farming classes. It has a long wooden handle and a thin razor-sharp curved blade at one end. It makes a formidable weapon even against the most determined enemy. Used in pairs they were flexibly reversed in the hand for both slashing and striking in a great many directions. If, however, the modern sickle resembles the ones used by the feudal farming class, it is apparent that one single blocking technique would sever the blade from the shaft and make it useless.

(The Shureido kama, above, has blades 3/16" thick and sturdy red oak shafts to withstand the rigors of kobudo. The shafts have been wrapped where they come in contact with other weapons. It is, however, very heavy to use and requires consistent training to strengthen one's hands and avoid flying, sharpened kama!)

Once again it is probable that more sturdy kama were constructed for fighting - although farming ones were no doubt also used. The techniques of this weapon are not often seen in modern times and there are only two registered kata in Japan today, called Kanigawa and Tozan.
-Michael Finn, Martial Arts: A Complete Illustrated History, The Overlook Press, 1988