An almond is not a nut, and California grows most of them
Botanically, the almond is the seed of a drupe, a cousin of the peach whose fleshy layer has shrunk into a leathery hull. About 80 percent of the world's supply comes from California, where heavy water demand during persistent drought has left some growers quitting and raised doubts about whether the industry can last.
The almond tree belongs to the genus Prunus and shares the subgenus Amygdalus with the peach, marked by the grooved woody shell around the seed. In plums and cherries the outer layers of the fruit are juicy; in the almond they form a grey-green, downy hull. Inside sits a hard, netted shell resembling a peach stone, and inside that the edible seed, usually one but occasionally two. When ripe the hull splits, and growers use mechanical shakers to bring the crop down.
It was among the earliest fruit trees people domesticated, partly because good trees could be raised straight from seed without grafting or cuttings. Archaeologists have found domesticated almonds at Early Bronze Age sites in the Middle East, and cultivation spread around the Mediterranean and similar dry climates with cool winters. The species is now rarely found wild in its original range.
The tree is modest, around 3 to 4.5 metres tall, with fragrant white to pale pink flowers that appear before the leaves in early spring. Its buds need a winter chill of 200 to 700 hours below 7.2 degrees Celsius to wake from dormancy, and it grows best between 15 and 30 degrees. Orchards produce a commercial crop from the third year and reach full yield after five or six, with fruit maturing in autumn seven to eight months after flowering. Refrigerated processed almonds keep about a year; warmth turns them rancid faster.
Even the scientific name has a saga. Linnaeus called it Amygdalus communis in 1753, and August Batsch moved it into Prunus in 1801 as Prunus amygdalus. In 1967 David Allardice Webb renamed it Prunus dulcis on priority grounds, lamenting the change after 165 years, but that name had already been given to a cherry in 1878. So the oldest valid name remains Prunus amygdalus.
Source: Almond
