Xanthium strumarium is a rather curious plant, especially considering it belongs to the daisy family. It has formed a large colony amongst other weedy species, where the small river crosses the beach in Skopelos town. The plant is easily recognised by its prickly bur-like fruits. The greenish  flowers are small and inconspicuous and short-lived; they rapidly develop into the burs.

The origin of the plant is much debated: it is often considered to have been introduced into the Mediterranean from North America, but there is pollen evidence which indicates its presence in Northern Greece just after the last ice age; this would confirm it as a native plant. The leaves have been used as a source of yellow dye, which has in the past been used to colour hair and it has been advocated as a herbal remedy for a variety of ailments. It can, however, become an invasive weed which is particularly troublesome if it infests the cotton fields of Greece.