据贵州省林业厅1981年的统计,全油桐衰老林(26年生以上)42万亩,占全省油桐总面积10％左右,产量亦占10％左右。如何作好老林更新,乃是我省油桐生产中急待解决的问题 之一。据有关资料报导,目前油桐更新有预植更新(在黔东北、黔北桐农长期间作区多采用)、截枝更新(在湖南湘西采用)等方式,至于伐桩更新虽有报导, According to the statistics of Guizhou Provincial Forestry Department in 1981, there are 42 million mu of all-tamarind forest (over 26 years of age), accounting for about 10% of the total area of ​​Tung oil in the province, and the output also accounts for about 10%. How to make a good old forest renewal, but is our province tung tree production one of the problems to be solved urgently. According to the information reported, the current tung tree updated with a pre-planting update (in northeast Guizhou, Guizhou Tong long-term use of area for a long time), cuttings update (used in Hunan Xiangxi), etc.,