Where the shape comes from
Loose grains lying on the threshing floor: four dots of husked rice scattered on either side of the crossed frame. It marks grain and things milled or ground from it — 米饭, 粉, 糖 — and is not the same picture as the growing plant 禾.
汉字 filed under 米
No published character on HSK Guide is filed under this radical yet. 汉字库.