The lemon is a species of small evergreen tree native to Asia. The first substantial cultivation of lemons in Europe began in Genoa in the middle of the 15th century. Lemon juice, rind, and zest are used in a wide variety of foods and drinks. Lemon slices and lemon rind are used as a garnish for food and drinks. Lemon zest, the grated outer rind of the fruit, is used to add flavor to baked goods, puddings, rice, and other dishes. Lemon oil may be used in aromatherapy. Lemon oil aroma does not influence the human immune system, but may enhance mood.[