根据林业部颁发的《选择育种技术要领》规定:“母树林是在天然林或人工林优良林分的基础上,经过留优去劣的疏伐改造,生产遗传品质较好的林木种子”。明确规定了母树林首先要选择优良林分,同时也必须认真的进行疏伐,只有这样,才能生产遗传品质好的林木种子。从七十年代中后期开始,全区有组织有计划的进行母树林建设。 According to the “Essentials of Breeding Breeding Techniques” issued by the Ministry of Forestry, “Mother trees are reforested on the basis of good stands of natural forests or plantations, and the forest seeds with better genetic quality are produced through thinning and transformation to improve the quality of trees.” Clearly stipulated that the first priority should be given to selecting good stands of mother trees, and at the same time, careful clearance must be carried out. Only in this way can forest seeds with good genetic quality be produced. Since the middle and late 1970s, the whole region has organized and planned mother tree construction.