new agricultural techniques were gradually introduced to the kanto from western japan , including irrigation techniques that utilized the planting of two crops a year , oxen and horses to plow , and water wheels , as well as increased production and use of manure fertilizer , leading to improved crop production; moreover , more concentrated and diverse agricultural efforts were launched thanks to advances in agricultural technology , which led to the development of a system of villages that spurred the growth of self-reliance among farmers . 西日本から関東地方に波及した二毛作の技術や牛馬耕、水車などを利用した灌漑施設の整備や肥料の発達などは生産力を向上させ、さらに農業技術の進歩で集約的・多角的な農業を行い、自立農民の成長を促して郷村制の成立をもたらす。