河西沙枣

河西沙枣

　　Elaeagnus angustifolia, also known as osmanthus willow, fragrant willow, and silver willow, is referred to by the people of the Hexi region as the "tree of a hundred treasures" — a fitting name indeed. Its fruits are rich in nutrition, deliciously sweet, its blossoms provide premium nectar, and its leaves serve as forage for poultry. The fruit, flowers, branches, and leaves can all be used in medicine, while the wood makes excellent material for high-grade furniture and handicrafts.

　　 Elaeagnus angustifolia, also known as osmanthus willow, fragrant willow, and silver willow, is called the “tree of a hundred treasures” by the people of Hexi. This is truly well-earned: its fruit is nutritious and tasty, its flowers are excellent nectar sources and feed for poultry, its fruits, flowers, branches and leaves are all medicinally useful, and its timber is ideal for making high-end furniture and artisan goods.

　　 　　Elaeagnus angustifolia (also known as osmanthus willow, fragrant willow, and silver willow) is mainly distributed across the northwestern provinces and autonomous regions of China, as well as western Inner Mongolia. Small amounts are also found in northern North China and western Northeast China, generally north of 34 degrees north latitude. Natural stands of Elaeagnus angustifolia are concentrated along the Tarim River and Manas River in Xinjiang, the Shule River in Gansu, and both banks of the Ejin River in Inner Mongolia. Some major river deltas within Inner Mongolia, such as Li Huazhong Tan and Da Zhong Tan along the Yellow River, also host populations. Inland riparian Elaeagnus forests are typically open and spread over large areas — just the Xihé Forest Area along the Ejin River contains over 69,000 mu of Elaeagnus woods. Cultivated Elaeagnus forests are widespread in Xinjiang, Gansu, Ningxia, Shaanxi, and Inner Mongolia. Especially in southern Xinjiang, the Hexi Corridor in Gansu, Zhongwei in Ningxia, Bayannur and Alxa leagues in Inner Mongolia, and Yulin in Shaanxi, large-scale farmland shelterbelts and windbreak-sand fixation forests have been planted with Elaeagnus. In recent years, provinces such as Shanxi, Hebei, Liaoning, Heilongjiang, Shandong, and Henan have also introduced and cultivated Elaeagnus in sandy wastelands and saline-alkali soils. Internationally, it is found around the Mediterranean, western Asia, the former Soviet Union, and India.

　　 　　Elaeagnus angustifolia is a shrub or small tree that grows 3 to 10 (sometimes up to 15) meters tall. Its bark is chestnut brown to reddish-brown, glossy, and the trunk is often twisted. The branches are dense with thorns, and young shoots, leaves, flowers, and fruits are covered with silvery-white scales and star-shaped hairs. The leaves are petiolate, lanceolate, 4–8 cm long, with pointed or blunt tips and wedge-shaped bases. They are entire-margined, with a silvery-gray-green upper surface and a silvery-white underside. The flowers are small, silvery-white, and fragrant, usually borne singly or in clusters of 1–3 in leaf axils of twigs. The calyx is tubular-campanulate, typically with four lobes at the tip. The fruit is an oblong-elliptical drupe, about 1 cm in diameter, with a mealy flesh. The skin is initially silvery-white, but later the scales fall off, revealing a yellowish-brown or reddish-brown hue.

　　 　　Elaeagnus angustifolia is highly resilient, with strong resistance to drought, wind-blown sand, salinity, and poor soils. Natural stands occur only in desert and semi-desert regions where annual precipitation is below 150 mm, typically associated with shallow groundwater — growth suffers if the water table is deeper than 4 meters. The plant requires relatively high heat conditions, thriving in areas with accumulated temperatures above 10°C exceeding 3,000°C. When accumulated temperatures fall below 2,500°C, fruiting is sparse. Germination begins when active accumulated temperatures rise above 5°C, growth accelerates above 10°C, and flowering starts above 16°C. Fruits mainly form during peak summer heat when average temperatures exceed 20°C. It shows strong salt-alkali tolerance, though this varies by salt type — it adapts better to sulfate-rich soils than chloride-heavy ones. It can grow where sulfate soil salt content is below 1.5%, but not where chloride salt exceeds 0.4%. Elaeagnus has an extensive lateral root system and a wide root spread, capable of producing numerous root nodules in loose soil. Nitrogen-fixing bacteria in these nodules enhance soil fertility. Lateral branches sprout vigorously, but terminal buds grow weakly. The dense branching habit leads to compact thickets. Branches buried by sand readily produce adventitious roots, contributing to windbreak and sand stabilization functions. In the Hexi Corridor of Gansu, sap begins to flow in late March, bud break starts mid-April, flowering occurs from late May to early June for about three weeks, young fruits appear in early July, fruits mature in shape by late August, and are fully ripe by October, with a fruiting period of about 100 days. Phenological phases in Xinjiang and Ningxia are similar to those in the Hexi Corridor, while central Inner Mongolia experiences slightly delayed timing. Through selective breeding, several superior Elaeagnus cultivars have been developed by local communities.

　　 　　As forage, Elaeagnus angustifolia has a long history of use in northwest China. Its leaves and fruits are high-quality fodder for sheep, which enjoy them year-round. Feeding sheep with Elaeagnus fruits not only helps fatten them but also improves ewe estrus and ram mating rates, aiding reproduction. During winter storms in the northwest, Elaeagnus groves provide shelter to protect sheep herds. It can also feed pigs and other livestock, beneficially promoting weight gain and milk production. Nutritionally, its leaves and fruits contain essential nutrients for livestock. Beyond fodder, Elaeagnus is also valuable for afforestation, landscaping, fuelwood, and as a windbreak and sand-fixing species. Elaeagnus powder can be used to brew wine, vinegar, soy sauce, and jams, with leftover pulp still suitable as feed. The fragrant flowers are excellent bee forage, containing aromatic oils for extracting fragrances and flavorings. Tree sap can be refined into Elaeagnus gum, a substitute for gum arabic. The flowers, fruits, branches, and leaves also have medicinal uses, treating burns, bronchitis, indigestion, and neurasthenia. The plant’s diverse economic applications have drawn wide attention, making it one of the major afforestation species in northwestern China. From a forage perspective, Elaeagnus holds significant importance in establishing artificial forage forests.