榆樹，喬本一種，雙子葉植物中屬榆科，主要喺北半球嘅溫帶地區生長。一般高約25米，樹皮粗糙。具高度實用、葯用及食用價值。
Elm, a species of joben, belongs to the family Ulmus in dicots, and grows mainly in temperate regions of the northern hemisphere. It is generally about 25 meters tall and has rough bark. It has a high degree of practical, medicinal and edible value.