Escape of Coreopsis tinctoria in northern Iran: Evidence from Gilan Province

During surveys of alien plants conducted in Guilan Province (northern Iran) from ۲۰۲۱ to ۲۰۲۶, eight ornamental species occurring outside cultivation were identified and monitored. Species identification was based on regional and international floras. Among these species, Coreopsis tinctoria exhibited the most pronounced spatial expansion and was the only taxon that developed multiple self-sustaining populations. C. tinctoria, an annual ornamental species native to North America, is widely cultivated for its attractive flowers. Escaped populations were recorded along roadsides, abandoned lands, drainage canals, urban margins, and disturbed grasslands, where they were mainly associated with ruderal vegetation. Field observations revealed different stages of establishment, ranging from isolated individuals and small colonies of up to ۳۰ plants to large colonies comprising approximately ۲۰۰ flowering individuals. The persistence of populations and successful seed reproduction over several consecutive years confirm the establishment of self-sustaining populations in the study area. The successful establishment of C. tinctoria is likely associated with its widespread ornamental cultivation, high reproductive capacity, and ability to colonize habitats disturbed by human activities. Compared with the other monitored ornamental species, C. tinctoria was the only species showing a clear pattern of escape from cultivation, successful establishment, and gradual spread across the region. This study provides the first documented record of the escape of C. tinctoria from cultivation in Iran and highlights the importance of monitoring escaped ornamental plants for the early detection of potentially invasive species in the Hyrcanian region.

کلیدواژه ها:

Alien flora ، Asteraceae ، naturalization ، Hyrcanian region ، ornamental plant ، ruderal