What is this anime with the power to change garbage into a tree? I think I watched it around the late 90s or early 2000s, and I think it's pretty popular. It's a shounen about male protagonist that can convert garbage into trees or leaves to make a weapon. Later he has the power to recycle his leaf into garbage and later turn it again into a leaf. There's also a man, I think an enemy of the protagonist's, that can change fabric into iron and become his weapon.

What is this anime?
The anime you're looking for is The Law of Ueki.