Tania 13 Flora

Rainforest Flora
There is a great variety of plants in the rainforest. More than two thirds of the world's different plants are found in tropical rainforests.
Rainforest plants have to struggle to survive because there is limited light, space and food. Many plants have different ways to help them survive. These include using other plants for support, having brightly coloured flowers or scent t and growing special root systems.
A species of plant that uses another plant for support is Epiphytes. These plants live on air but grow on the trunks, branches and leaves of trees. Some epiphytes include orchids, cacti, bromeliads, lichens, mosses and ferns. They begin their life in the canopy from seeds or spores carried there by birds, animals or winds.
Bromeliads have thick, waxy leaves that have a round shape in middle for holding water. It also gives a home for several creatures including frogs, tadpoles, snails and beetles. When these animals die they provide nutrients for the plant.
One type of epiphyte is an orchid. There are many different varieties of orchids (up to 20,000 known species). Orchids have different shapes, colours and size but all orchids have three petals. Not all orchids are epiphytes - usually only the ones in tropical areas. In the temperate areas they usually grow in the soil. Orchids are usually brightly coloured to attract animals to help them pollinate.

Some plants like the Strangler Fig live on other trees but end up killing it. A Strangler Fig starts to grow like an epiphyte but lets down its roots. When the roots touch the ground the fig quickly starts to grow until it kills the other tree.

Lianas (climbing vines) are tangled, woody climbing plants that use other plants for support. They come in a variety of lengths and sizes. Unlike epiphytes they start to grow on the forest floor and climb upwards towards the sunlight using the trunks of other trees for support. When they reach the top of the canopy they often spread to other trees or other lianas. Ninety per cent of the world's vine species grow in tropical rainforests.

Another way rainforest plants have changed to their environment is by having different root systems. Some very tall trees have buttress roots. These are roots which grow out from the bottom of the trunk. They can be over four metres above the ground. Without these huge roots to support their size and weight the trees would over balance. These soils big roots also mean that there is a wider area form which the tree and get food.
Mangroves have different roots, their roots point up out of the ground. They grow in wet, muddy soil at the water's edge where there are tides or flooding.

The curtain fig has a root system that covers a wide area and looks like a curtain.
Some trees in a rainforest protect themselves by being poisonous or having stinging parts. The Stinging tree in Australia grows to a height of up to 30 metres. It large, bright green leaves have holes from insects and it has fine spines that are poisonous. The Lawyer Cane is also has needle sharp spikes.

Saprophytes don’t need the sun. They turn dead and decaying matter into nutrients for other plants to use. Some are so small that they can’t be seen with the naked eye. Saprophytes include mushrooms and other fungi. Carnivorous plants are special plants that get their food from animals. The Venus fly trap has tiny hairs in the middle and when an insect or spider crawls along the leaves and touches these hairs the trap closes. Another carnivorous plant is the pitcher plant which is found in Southeast Asia. This has a tube that fills with liquid to make a trap.

Plants in the rainforest are very important because they give shelter and food for rainforest animals. They also help the environment by using carbon dioxide and replacing it with oxygen. Many of the different species of plants in the rainforest are also used in medicines.

References


http://pro.corbis.com/images/WK017569.jpg?size=67&uid=834766FA-1125-4B65-B9A9-51942E071607
http://www.srl.caltech.edu/personnel/krubal/rainforest/Edit560s6/www/plants/saprophytes.html
Jones Stephen Rainforests
Paris Steve Australian Forests and Woodlands