Pistachio

The pistachio ("Pistacia vera") is a small tree from the family Anacardiaceae (also known as the Cashew family). It is well known for its seeds that are eaten as food. It is native to the Middle East and Central Asia.
The plant.
The tree grows up to tall. Its leaves are 10–20 centimeters (4–8 inches) long.
The fruit is a stone fruit. Only the seed is edible. The fruit has a hard, cream-colored exterior shell. The seed has a mauve-colored skin and light green flesh. When the fruit ripens, the shell goes from green to yellow or red and splits a bit open. Different varieties split differently.
Pistachio trees can give of seeds on average every two years.
The shell of the pistachio is naturally a beige color, but it is sometimes dyed red or green. It is thought that dye was used by importers to hide stains on the shells when the seeds were picked by hand. Most pistachios are now picked by machine and the shells do not have stains.