Promotion to Farmers of Snow Compaction (Yuki-Fumi) on Winter Wheat to Control Volunteer Potatoes without Depending on Chemical Materials

Adaptation to climate change in response to changes in snow cover has led to the development of snow control technology on agricultural fields in Hokkaido. In the control of the soil frost depth and freezing to death of potato tuber leftovers in harvesting during the subsequent cultivation, winter wheat has been an effective countermeasure in crop rotation systems in Hokkaido. We investigated a method used to control soil frost depth by snow compaction (yuki-fumi) to balance between killing potatoes and growing winter wheat. In an experimental test in NARO, we found that snow compaction has a negative effect on wheat growth at a very early stage of the snow cover. Snow compaction does not reduce soil temperatures as much as snow removal, but in potato-to-wheat rotation, it reduced volunteer potatoes by 1/10 because of the shallow position of unharvested potatoes. Snow compaction on wheat can control volunteer potatoes without depending on pesticides and does not adversely affect wheat growth. These environment-friendly agricultural systems have gradually become widespread in eastern Hokkaido.