Why were the border states important to both sides in the civil war?

Border states were slave states in the civil war that didn't abandon the Union, so these states helped the union by providing in advantage in money, factories, and troops in which played a huge role in the victory of the Union. 

Texas’ gulf coastal plains are the western extension of the coastal plain extending from the atlantic ocean to beyond the rio grande. its characteristic rolling to hilly surface covered with a heavy growth of pine and hardwoods extends into east texas. in the increasingly arid west, however, its forests become secondary in nature, consisting largely of post oaks and, farther west, prairies and brushlands.