Toya potatoes have reddish leaves at the time of sprouting, stem length is slightly longer than “Baron potato”, and the plant is slightly upright. The stems are thick and few in number. The stem color is green and there seems to be a reddish purple distribution at the base. The stem wings are straight and less branched. The leaf color is slightly pale green, and the leaflets are wide, large, glossy, thick, and somewhat bumpy. The leaflets are slightly sparsely attached, and the whole is rough. The flowers are white and medium in size. There is a lot of pollen, and the natural results are moderate.
Rusutsu Village is the birthplace of the Benimaru Potato variety for starch. In 1929, at the Hokkaido Agricultural Research Center (Kotoni, Nishi Ward, Sapporo City), this variety was selected from a cross between a Lembke Frühe Rosen potato as a mother and a Pepo potato as a father. In 1938, it was tested under the strain name of “Honiku No. 309 Potato”, and in 1938, it was decided to be an excellent variety and named as a limited variety for starch in the foothills of Mt. Yotei. According to records such as “Potato Benimaru” (published in 1972), Yuji Masuda and Mataro Onishi visited the Hokkaido Agricultural Experiment Station in April 1932, and later opened “Benimaru Potato”. It seems that he brought back 6 to 7 “Honiku No. 309 potatoes” and cultivated them on a trial basis in the field of Masuda in Rusutsu Village.
Benimaru potatoes have a high yield and a high starch value, and spread throughout Hokkaido as the main variety for starch. 14,000 hectares in 1941, 36,000 hectares in 1944, and 58,000 hectares in 1949 as a variety that can withstand the worst conditions without labor. , Most of the cultivars used as starch raw materials were replaced by Benimaru potatoes, and it seems that they were even cultivated for food. In addition, it is recognized that it is suitable not only for Hokkaido, but also for back crops in high-temperature areas and paddy fields in other prefectures. At that time, Kagawa Prefecture was the only prefecture whose crops did not appear in the statistics, and it is still talked about today that it contributed significantly to alleviating food shortages during and after the war. Together with “Nourin No. 1 potato”, which was born in 1943, both varieties were cultivated until the beginning of 1985 while firmly maintaining their position as a variety for starch seems to be declining rapidly.