Why is it important to know the division or phylum of the various plant species growing in your backyard?

It is important to know the division or phylum of the various plant species growing in your backyard so as to determine whether they will spread and ruin other crops and plants of yours. Not every plant is beneficial, so you need to know which ones to keep, and which to deplant.

Iguess i would say diagrams would be most difficult subject too correct