Tree Zone Area 1
From the Super Mario Wiki
The player starts at a stretch of flat land, leading to what is presumably the roots of a tree. On these roots there are several gaps in the roots which contain several Bopping Toadies and Ragumo, that also appear on top of the roots. Later in the level several Kyotonbo and Spikeys appear to block the player. On the roots there is several Hidden Blocks which lead to a 1-Up Heart, and inside the roots lays a ? Block which contains a either a Fire Flower or a Mushroom. After the ? block is the levels checkpoint Bell. After the bell the roots form a tree. Inside the tree is a Ragumo, several coins and twelve ? blocks eleven of which have coins with the one other containing either a Mushroom or a Fire Flower. On the top of the tree (which must be climbed in order to complete the level) there is a Kyotonbo. After the tree there is several other sets of enemies, and three blocks which lead to the end of the level.