<P> Archaeology shows that pistachio seeds were a common food as early as 6750 BC . Pliny the Elder writes in his Natural History that pistacia, "well known among us", was one of the trees unique to Syria, and that the seed was introduced into Italy by the Roman Proconsul in Syria, Lucius Vitellius the Elder (in office in 35 AD) and into Hispania at the same time by Flaccus Pompeius . The early sixth - century manuscript De observatione ciborum ("On the observance of foods") by Anthimus implies that pistacia remained well known in Europe in Late Antiquity . Archaeologists have found evidence from excavations at Jarmo in northeastern Iraq for the consumption of Atlantic pistachio . The Hanging Gardens of Babylon were said to have contained pistachio trees during the reign of King Merodach - Baladan about 700 BC . </P> <P> The modern pistachio P. vera was first cultivated in Bronze Age Central Asia, where the earliest example is from Djarkutan, modern Uzbekistan . It appears in Dioscurides as pistakia πιστάκια, recognizable as P. vera by its comparison to pine nuts . </P> <P> Additionally, remains of the Atlantic pistachio and pistachio seed along with nut - cracking tools were discovered by archaeologists at the Gesher Benot Ya'aqov site in Israel's Hula Valley, dated to 780,000 years ago . More recently, the pistachio has been cultivated commercially in many parts of the English - speaking world, in Australia, and in New Mexico and California, of the United States, where it was introduced in 1854 as a garden tree . David Fairchild of the United States Department of Agriculture introduced hardier cultivars collected in China to California in 1904 and 1905, but it was not promoted as a commercial crop until 1929 . Walter T. Swingle's pistachios from Syria had already fruited well at Niles, California, by 1917 . </P> <P> Pistachio is a desert plant and is highly tolerant of saline soil . It has been reported to grow well when irrigated with water having 3,000--4,000 ppm of soluble salts . Pistachio trees are fairly hardy in the right conditions and can survive temperatures ranging between − 10 ° C (14 ° F) in winter and 48 ° C (118 ° F) in summer . They need a sunny position and well - drained soil . Pistachio trees do poorly in conditions of high humidity and are susceptible to root rot in winter if they get too much water and the soil is not sufficiently free - draining . Long, hot summers are required for proper ripening of the fruit . </P>

Where do pistachio trees grow in the u s