Why don't Hindus plant more trees? Isn't it a part of Karma since we use a lot of wood for cremation of dead?

It's not enough that most Hindus follow vegetarianism but we should be planting more trees as well since at the end of our lives we use a lot of wood for cremation. To balance Karmic law we should be planting more trees, right! Our environmental impact in our lives is still lower than other religions but we should be doing even more. Guru Ramdev asked people to plant a tree on every Birthday, Isn't that a good idea that should be followed.