Why do ferns leave only one branch?

Plants will grow more luxuriantly because of the need to concentrate nutrients. Pteris monocarpa is a perennial evergreen herb with high ornamental value. In the process of breeding, reasonable pruning is needed to promote the growth of plants. When pruning, only one branch needs to be kept, and this branch will become the main branch, so that nutrients can be supplied to the main branch and plants can grow more luxuriantly.