中文摘要：

北京天坛作为明清封建帝王时期最高等级的祭祀场所，是建筑与景观完美结合的设计杰作。天坛外坛通过其特有的植物景观烘托出祭坛庄严肃穆的氛围，是天坛完整性的重要组成部分。通过查阅籍资料与调研现状古树，分析阐明了明清时期天坛外坛植物由圆柏、侧柏、油松、国槐、银杏、柳、愉树、榔愉、牡丹、益母草等乡土植物构成，呈现郊野风貌，植物景观特征独具祭坛特色。对整治天坛外坛植物，恢复天坛历史原貌具有重要指导意义。

英文摘要：

The Temple of Heaven in Beijing, as the highest grade of the worship places during the period of Ming and Qing feudal emperors, is a masterpiece, the perfect combination of architecture and landscape design. The altar outside the Temple of Heaven through its unique plant landscape foil gives the altar solemn atmosphere, and is an important part of the integrity of the Temple of Heaven. This article consulted ancient materials, and researched status of ancient trees, elucidated plant in the altar outside the Temple of Heaven born by the indigenous plant composition, Sabina chinensis, Platycladus orientalis, Pinus tabulaeformis, Sophora japonica, Ginkgo biloba, Salix matsudana, Ulmus pumila, Ulmus parvifolia, Paeonia suffruticosa, Leonurus artemisia, etc, presented country style, and plant landscape features had the unique altars characteristics, during the Ming and Qing dynasties. This study has the important instruction meaning for regulation of plants in the altar outside the Temple of Heaven, and to restore the original appearance of the Temple of Heaven.