The pistachio (Pistacia vera L., Anacardiaceae; sometimes placed in Pistaciaceae) is a small tree up to 10 m tall, native to mountainous regions of central and southwestern Asia such as the Kopet Dag mountains of Turkmenistan southwest to northeastern Iran and western Afghanistan. It has deciduous pinnate leaves 10–20 cm long.
The plants are dioecious, with separate male and female trees. The flowers are apetalous and unisexual, and borne in panicles. The fruit is a drupe, containing an elongated seed (a nut in the culinary sense, but not a true botanical nut) with a hard, whitish shell and a striking light green kernel, having a characteristic flavour.
When the fruit ripens, the shells split open partially (see photo). This happens with an audible pop.
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