A woman is threshing rice stalks with a Senbakoki (åƒæ¯æ‰±ã, threshing machine), while a man is carrying straw bags balanced on a pole. In the back drying rice plants can be seen, it was customary to dry freshly cut rice plants before threshing commenced.
There aren’t that many photographs on the Old Photos of Japan website dealing with agriculture, but this is a great one, and the explanatory notes describe the rice cultivation calendar and point to a useful wikipedia article on Agriculture in the Empire of Japan. Would be interesting to match up with Vavilov’s observations on Japanese agriculture.