Where are the main production areas of Sichuan pepper currently?
The production areas of Sichuan pepper stretch from southern Northeast China in the north, to the northern slopes of the Five Ridges in the south, to the coastal areas of Jiangsu and Zhejiang in the southeast, and to southeastern Tibet in the southwest; it is not produced in Taiwan, China, Hainan or Guangdong. It is found from plains to higher-altitude mountain areas; in Qinghai, it is found on slopes at an altitude of 2500 m, and is also cultivated.
Sichuan pepper is suited to warm, humid conditions and deep, fertile loam or sandy loam. It has strong suckering ability, is cold-resistant and drought-tolerant, loves sunlight, has strong disease resistance, and its dormant buds have a long lifespan, so it tolerates heavy pruning. It is not tolerant of waterlogging; short-term water accumulation can cause death.
Oil-leaf Sichuan pepper
The leaflets have oil dots visible to the naked eye; the oil dots become slightly raised after drying, and the leaf rachis, infructescence and mericarps turn reddish brown after drying. Fruiting period is July-August. The leaflets are hairless except for tufts of hair on both sides of the base of the midvein on the underside, and apart from oil dots along the leaf margin, the leaflets have no other oil dots.
Oil-leaf Sichuan pepper is produced in western Sichuan (Tianquan, Eshan and other places), in sparse mountain forests at an altitude of 2000-2500 m.
Hairy-leaf Sichuan pepper
New young branches, the leaf rachis and inflorescence rachis, and both surfaces of the leaflets are covered with soft hairs, though sometimes the fruit stalk and the upper surface of the leaflets are hairless. This variety is divided into two types: in one type, the leaflets are thin and papery, and after drying the two surfaces differ markedly in color, with the underside pale grayish white, and the fruit stalk slender and elongated; in the other type, the leaflets are thick and papery, the leaf surface and fruit stalk are hairless, the lateral veins are sunken on the leaf surface and form fine fissure-like grooves, the two surfaces of the leaflets are nearly the same color, turning reddish brown after drying, and the fruit stalk is relatively thick. Flowering period is May-June, fruiting period is October-November.
Hairy-leaf Sichuan pepper is produced in Qinghai (Xunhua), Gansu, southern Shaanxi, and western and northwestern Sichuan (Li County, Heishui, Mao County, Baoxing and other counties). It is found in mountain areas at an altitude of 2500-3200 m.