Argania is a genus of flowering plants containing the sole species Argania spinosa, known as argan, a tree endemic to the calcareous semidesert Sous valley of southwestern Morocco. Argan grows to 8–10 m high and lives up to 200 years. They are thorny, with gnarled trunks. The leaves are small, 2–4 cm long, and oval with a rounded apex. The flowers are small, with five pale yellow-green petals; flowering is in April. The fruit is 2–4 cm long and 1.5–3 cm broad, with a thick, bitter peel surrounding a sweet-smelling but unpleasantly flavoured layer of pulpy pericarp. This surrounds the very hard nut, which contains one (occasionally two or three) small, oil-rich seeds. The fruit takes over a year to mature, ripening in June to July of the following year.