西峡油桐

    油桐因树似梧桐 、种子可榨油（称桐油）而得名。树高4～10米。小枝粗壮，无毛。单叶互生，心脏形或阔卵形，全缘，叶柄圆形，顶端与叶片连接处有2个紫色腺体。单性花，雌雄同株，间有异株，白色，基部有淡红色斑纹。核果球形或扁球形，果皮光滑。中国产的另一种木油桐树形高大，外果皮有3～4纵棱，并有许多皱纹。有时油桐是这两种的泛指。 世界上种植的油桐有6种，以原产中国的三年桐和千年桐最为普遍。油桐属大戟科，落叶乔木。三年桐学名油桐，长得快，结果早，产量高，盛果期可达20 年～30年。千年桐学名木油桐，因果皮有皱纹，又称龟背桐，寓意长命百岁。千年桐比三年桐高大，有10多米，树龄较长。油桐种子榨出的油叫桐油；木油桐种子榨出的油叫木油，质量稍逊。
      
    油桐喜光 。喜温暖 ，忌严寒 。冬季短暂的低温(－8～－10℃)有利于油桐发育 ，但长期处在－10℃以下会引起冻害。适生于缓坡及向阳谷地，盆地及河床两岸台地。富含腐殖质、土层深厚、排水良好、中性至微酸性沙质壤土最适油桐生长。油桐栽培方式有桐农间作、营造纯林、零星种植和林桐间作等。
      
    桐油是重要工业用油，制造油漆和涂料，经济价值特高。桐油和木油色泽金黄或棕黄，都是优良的干性油，有光泽，不能食用，具有不透水、不透气、不传电、抗酸碱、防腐蚀、耐冷热等特点。


 

Tung Oil Tree

    Tung oil tree gets this name for it's similar with Chinese parasol tree and its seeds can be used to make oil. It height varies from 4 m to 10 m with thick and solid branches and no hair. Its flowers are in the same sex and white color commonly. Tung oil tree likes light, warmth and hates cold climate. Short time low temperature (above subzero 10) in winter will be helpful for its growing, while if the temperature reaches below subzero 10, it will be hurt. Slight slope and sunny valley, basin and shores of rivers are appropriate for its growing, which had better be full of humus, normal to acidic sandy loam, and have thick soil and good dewatering quality. It cultivating methods are trees and crops intercropping agriculture, only planting trees, planting sporadicly, forest and trees interplanting and so on. Tung oil it produces is an important industrial oil which can be used to make paint and coating and contains much high economic values.