**2. The fertilizer market in the beginning of the twentieth century in Japan**

The Meiji period started in 1868 and ended in 1912. During this period, the Japanese people eagerly took in new ideas about culture and civilization from the Western countries. It was towards the end of the Meiji period when Oyaizu and Daikuhara crossed paths. At that time, new developments in agricultural technology and transportation had increased the demand for fertilizer. To meet the demand, new types of commercial fertilizers such as soybean meal, animal bone meal and chemical fertilizers were being imported into Japan [15].

In spring of 1896, Mr. Yasuie Suzuka, who was the president of fertilizer trading company, was taught by Dr. Jun Sawano, who was the first director of the Imperial Agricultural Experiment Station, that ammonium sulfate was a promising fertilizer and worth importing. Suzuka then imported 5 tonnes of ammonium sulfate for the first time from Australia [15]. In the beginning, however, it was difficult to sell the ammonium sulfate "medicine" to fertilizer dealers [16]. To ensure the quality of ammonium sulfate and enlarge its market, Suzuka relied on fertilizer testing services offered by the Imperial Agriculture Experiment Station [15].

Fertilizer testing services had been available since the founding of the station in 1893 [17]. The Fertilizer Regulation Act was put into operation in 1901, and the number of requests increased rapidly. The number of employees at the station increased, and a method for fertilizer analysis was established. The book *Standard methods in agricultural chemistry* [18] identified the follow‐ ing properties to be tested: moisture, ash, organic matter, nitrogen, phosphorus and potassium. The concentrations of nitrogen, phosphorus and potassium in a fertilizer were regarded as the most important properties.

From the 1900s to the 1930s, the ammonium sulfate market in Japan shifted from importation to domestic production. In 1902, sales of commercial fertilizers was largest for soybean meal (28% of the total amount), which was followed by fish meal of herring and sardine (27%), chemical fertilizers (14%) and rapeseed oil cake (13%) [19]. Chemical fertilizers included superphosphate, ammonium sulfate and sodium nitrate, but the percentage of their sales to the total amount was slightly more than 10%.

In the 1910s, the Haber-Bosch process of ammonia synthesis was invented in Germany. The rapid German commercialization of the Haber-Bosch process, however, was not followed by a similarly rapid conquest of the world fertilizer market [20]. In 1913, Chile, possessing huge deposits of sodium nitrate, was the largest producer of nitrogen in the world (56.5%) and Germany was the second (15.6%) [21]. At that time, Japan accounted for only 0.5% of world production. As shown in **Figure 2**, production increased rapidly thereafter. By 1934, Japan accounted for 10.5% of world production and had become the third largest producer in the world after Germany (23.5%) and the United States (13.0%).

**Figure 2.** Annual production of ammonium sulfate and superphosphate in Japan during the Taisho (1912–1926), Showa (1926–1989) and Heisei (1989–present) periods. The values were derived from data in several fertilizer hand‐ books published by the Association of Agriculture and Forestry Statistics, Tokyo.
