临安县昌北区栽培山核桃已有二百年历史。全区有山核桃林六万余亩,产量占全县一半。1979年达四万担,是产区社员经济收入主要来源。但山核桃存在始果期迟,大小年明显,产量不稳;树冠高大,采收困难;嫁接不易成活等弊病,影响了它的发展和经营管理程度。为了加速发展山核桃生产,改变半野生状态,达到“矮化、密植、早实、 Lin’an Changbei District cultivated pecan has two hundred years of history. The region has more than 60,000 acres of pecan Hulin, accounting for half of the county. In 1979 reached 40,000 Tam, is the main source of income of production members. However, there are early pecan fruit onset period, the size of the year is obvious, the output is unstable; crown tall, harvesting difficulties; grafting difficult to survive and other ills, affecting its development and management level. In order to accelerate the development of pecan production, change the semi-wild state, to "dwarf, dense planting, early fruiting,