Matricaria discoidea, synonym: Chamomilla suaveolens and Lepidotheca suaveolens; The pineappleweed also known as Mayweed is a plant that grows on soils which have been extensively influenced by human activities. Think of road sides, car parks etc. Having said this it is a usefull plant too. In the absence of Matricaria recutita (scented mayweed) on Iceland the flowers can be used in herbal tea's for its aroma. As a daisy family memeber and as a mayweed species it can be easily distinguished by the absence of ray flowers on the flower heads.
It is a member of the Asteraceae family (= Compositae ), the daisy family. The Icelandic name of this species is Hlaðkolla.