Common groundsel / Kostriš

It is a tenacious deciduous annual whose presence now encompasses the globe in a wide area of easy to somewhat difficult growing conditions.
The discussion of Common groundsel dates back to the 1st century and more recently, it is the subject of much contradictory and reactionary information about where it came from, how it got there, whether is it really hurting the crops, how to get rid of it, and how dangerous it is when ingested by various animals. Standing only between 10 to 41 cm tall, bright florets mostly hidden by the characteristic bract giving it the appearance of never opening flowers and with a life span of 5–6 weeks, the self-fertilizing Senecio vulgaris lives humbly among and occasionally under the other weeds and is easy not to notice. Open clusters of 8 - 10 small cylinder shaped rayless yellow flower heads 6 - 13 mm with a highly conspicuous ring of black tipped bracts at the base of the inflorescence as is characteristic of many members of the genus Senecio.