美国是一个移民国家L早期前往美洲的移民深受欧洲古典园林思想及生活方式的影响。中世纪的欧洲贵族、骑士、僧侣在宫殿、住宅、寺庙周围种植大面积的草坪，间以高大的乔木和开花的灌木，形成美丽的疏林草坪景观。因此，美国初期的城市绿化以草坪、花卉、树木及绿色墙篱为主，表 The United States is an immigrant country. Early immigrants to the Americas were deeply influenced by the ideas and lifestyles of European classical gardens. Medieval European nobility, knights, monks in the palaces, houses, temples planted around the large area of ​​lawn, between the tall trees and flowering shrubs, the formation of the beautiful sparse grass lawn landscape. Therefore, the initial United States urban greening with lawns, flowers, trees and green fence mainly table