1973年5月间,河南省偃师县大口公社韩村四队社员在给棉苗追肥时,用泡桐树叶垫篮子盛化肥后,将泡桐叶子丢在棉苗的行间,第二天一大早,发现这张泡桐叶下边有8条地老虎幼虫。当天傍晚,他们又放了24张泡桐叶试验,第三天早上检查,每张泡桐叶下面都有虫,最多一张叶下有29条。据他们试验,其他桐树叶子也可以利用。1974年,该公社普遍推广, May 1973, Henan Yanshi Dakout commune Hancun four team members to cotton seedling fertilizer, with Paulownia leaf pad basket Sheng fertilizer, the leaves of Paulownia lost in cotton seedling line, the next day a large As early as this, there were 8 land tiger larvae found beneath this leaf of Paulownia. On the evening of the same day, they released another 24 leaves of paulownia leaves and checked on the morning of the third day. Each paulownia leaf had insects beneath it and up to 29 leaves under one leaf. According to their experiments, other tung leaves can also be used. In 1974, the commune was widely promoted,