They felled great thickets of rhododendrons to make way for more novel exotics.他们砍倒了大片杜鹃花丛给新奇的外来植物腾地方。Immigrant plants are sweeping through the Cape of Africa, threatening to strangle the region's prized bush vegetation.外来植物正在非洲好望角蔓延，对该地区珍贵的灌木植被存活形成威胁。