生长在美国加利福尼亚州的北美红杉(Se-quoia sempervirens)林驰名全世界,通常这种树木能长到100多米高,寿命可长达200多年。而常被用作圣诞树和重要的木材资源花旗松(Pseudotsugamenziesii),也同样对加利福尼亚的环境和经济起着十分重要的作用,上述两种树木每年给美国带来将近十亿美元的经济收益。然而就在最近,科学家们发现在加利福尼亚南部两个地区生长的北美红杉和花旗松,迅速地被一种名为“突发橡树综合症” The Sequoia (Sequoia sempervirens) forest, which grows in California, is best known throughout the world and usually grows to more than 100 meters in height with a life expectancy of more than 200 years. Often used as a Christmas tree and as an important timber resource, Pseudotsugamenziesii also plays a very important role in the environment and economy of California, which generate nearly a billion dollars in economic benefits to the United States each year. More recently, however, scientists have found that S. sequoia and Douglas fir grown in two areas of southern California quickly became known as “sudden oak syndrome”