作为满洲民族特性“围猎骑射”在国家政治生活中的体现，南苑“例禁开田”长期被奉为“祖宗旧制”而恪守不变。然而，嘉道以后苑内私垦日甚一日，朝廷虽屡次查禁，严令抛荒，但最终徒具虚文。咸丰、同治二朝，不断有大臣以各种理由奏请放垦，只因这种着眼于经济民生的理由始终敌不过政治层面的“祖宗旧制” 而一再被否决。到光绪朝末年，南苑全面放垦。对于清廷而言，南苑是否放垦，绝非只是“足民食” 的经济问题，而是事关“立国之本”的政治原则问题。随着王朝败落，“祖宗旧制”最终让位于“足民食”的经济诉求。

The reclamation of land in the Imperial Garden Nanyuan was prohibited under“traditional ancestral Rule,”which reflected national Manchu characteristics of Archery hunting. Although the government frequently repeated the prohibition, these prohibition were ultimately ineffective. The phenomenon of private cultivation became more and more serious after the Jiaqing and Daoguang reigns and there had been proposals to cancel the ban for various reasons in the Xianfeng and Tongzhi reigns. Unfortunately，these proposals were repeatedly rejected，because ancestral rules were always more important than the people’s livelihood in the eyes of the Emperor. By the end of Guangxu reign, Nanyuan was fully opened, and the rules forbidding reclamation finally succumbed to economic pressure and peoples’livelihood. For the Qing Court, whether or not Nanyuan was reclaimed was a political rather than an economic problem，which related to the foundation of country. With the decline of Qing Dynasty, the ancestral rules finally gave way to economic demands．