Chrysanthemum boreale (or "Dendranthema boreale") is a flowering plant within the Asteraceae family and "Chrysanthemum" genus. It used to be in the compositae family and many books still contain as such. It is a perennial flowering plant that is often noted because of its yellow flowers. It has 18 chromosomes at the diploid stage.
It is extremely unlikely the number of chromosomes changes from one individual to the next