You have to pinch off the side shoots of the cotton plant.
Tips
usage
Read 杈 (falling tone) for the natural fork where a plant or tree branch splits - 树杈 (tree fork), 枝杈 (branch fork). The first-tone reading 杈 is a different word - a hand tool.
Left is the tree radical 木, placing the character among trees and timber. It tells you the splitting being described is in wood - where a branch divides off the trunk.
Right is 叉, a hand with a crossing stroke - both the sound and a strong meaning hint: a fork shape. Wood plus fork gives the branching point of a tree.
