DENDROLOGY

Detailed explanation-1: -The upper canopy is 100-130 feet above the forest floor, penetrated by scattered emergent trees, 130 feet or higher, that make up the level known as the overstory. Below the canopy ceiling are multiple leaf and branch levels known collectively as the understory.

Detailed explanation-2: -These layers are called forest storeys or strata. The top-most stratum is made of emergent trees; below them are the canopy trees, which are usually present as a continuous layer. The tree strata below them are called the sub-canopy and the understorey.

Detailed explanation-3: -Emergent layer. At the very top of the rainforest, a few trees considerably taller than all the rest stick up out of the greenery, like giants looking over the heads of a crows. These scattered tallest trees form what is called the emergent layer.