Elm is a kind of Ulmaceae. Mainly distributed in the north temperate zone, almost everywhere in China, but with different varieties. Among Ulmus plants, Ulmus plays a very important role in afforestation. Most of them live on river banks, hillsides and fields below 1000 meters above sea level. Elm likes light, has strong adaptability to climate, and is not very strict with soil. Elm has deep roots and fast growth. It grows very fast and well in sandy soil, with deep and fertile soil and sufficient water. In addition, elm is also very resistant to urban pollution, especially hydrogen fluoride and smog. Elms are often planted in courtyards or on both sides of roads, which can not only provide good shade, but also have good greening and vacuuming effects. Elm has high utilization value. Its trunk is straight and it is a good furniture material; Fruit, leaves and bark can be used as medicine, which can effectively relieve neurasthenia and insomnia symptoms, and is often used by people to soothe the nerves; If the bark is peeled off, it can also become a strong and durable rope. ...