Clopyralid is a synthetic plant hormone, its chemical structure and many natural plant hormone similar, but the plant
tissue having a better durability. It is mainly through the roots and leaves of the plant to absorb and conduction in plants,
so its conductivity is strong. Weed spraying, it is absorbed by the roots or leaves of plants, in plants move up and down
and quickly transmitted to the whole plant. Clopyralid low concentrations to stimulate the plant DNA, RNA and protein
synthesis leading to uncontrolled cell division and disorderly growth, leading to destruction bundle; clopyralid high
concentration it is possible to inhibit cell division and growth .