Abstract: The United States has conducted extensive plant introduction activities worldwide since the 19th century. Rhododendron species received particular attention due to their high ornamental value. In the 20th century, the United States focused particularly on Rhododendron resources in China. To clarify the history of the introduction of Rhododendron from China to the United States, we compiled historical records to trace the history of American Rhododendron introductions from China between 1898 and 2023, and verified the botanical names, introduction times, locations, and collectors. The results showed that a total of 1406 records of American Rhododendron introductions from China were compiled, including 215 species (including 27 varieties and 12 subspecies), which accounted for 29.5% of the total number of Rhododendron species in China. The introduction activities covered 20 provincial administrative regions, and 10 collectors were involved, with Wilson and Rock standing out for their significant contributions. The American introductions of Rhododendron from China enriched the diversity of Rhododendron species in the United States and enhancing their application in American gardens.

Key words: plant introduction, Rhododendron, introduction history, China, United States, germplasm resources