From the crowns to the floor

The layers

It is known for its dense canopies of vegetation that form three different layers. NASA The top layer or canopy contains giant trees that grow to heights of 75 m (about 250 ft) or more. This layer of vegetation prevents much of the sunlight from reaching the ground. NASA The middle layer, or understory, is made up of vines, smaller trees, ferns, and palms. NASA The bottom layer or floor of the rainforest is covered with wet leaves and leaf litter. This material decomposes rapidly in the wet, warm conditions, sending nutrients back into the soil. Few plants are found on the floor of the forest due to the lack of sunlight. NASA

Rainforests exhibit a highly vertical stratification in plant and animal development. The highest plant layer, or tree canopy, extends to heights between 30 and 50 metres. Britannica The next lowest layer of the rainforest is filled with small trees, lianas, and epiphytes, such as orchids, bromeliads, and ferns. Britannica Contrary to popular belief, the rainforest floor is not impassable. The ground surface is bare, except for a thin layer of humus and fallen leaves. Britannica The climate of the ground layer is unusually stable. The upper stories of tree canopies and the lower branches filter sunlight and heat radiation, as well as reduce wind speeds, so that the temperatures remain fairly even throughout the day and night. Britannica

Most of the trees are dicotyledons, with thick leathery leaves and shallow root systems. The nutritive, food-gathering roots are usually no more than a few centimetres deep. Britannica Most rainforest soils tend to be permanently moist and soggy. They are not very fertile, because the hot, humid weather causes organic matter to decompose rapidly and to be quickly absorbed by tree roots and fungi. Britannica

A large number of plants from the understory are used as common houseplants, NASA notes, and the majority of common houseplants come from the rainforest. NASA

The floor is not an impassable wall of greenery. That myth, and a few others, are on the myths page.