It is scentless mayweed, Tripleurospermum inodorum, often confused in the literature with scented mayweed or German chamomile, Matricaria recutita. In Gylfaginning 12th century Icelandic saga writer Snorri Sturluson explains that because of the whiteness of the petals scentless mayweed is called ‘Baldr's brow’ (Baldr was one of the Viking gods): “He is best, and all praise him; he is so fair of feature, and so bright, that light shines from him. A certain herb is so white that it is likened to Baldr's brow; of all grasses it is whitest, and by it you may judge his fairness, both in hair and in body.”
This plant, or its smellier sister, have been said to cure many afflictions, perhaps drawing on Baldr’s virtues. Both are also frequently confused with true chamomile, Chamaemelum nobile and related plants. It is probably the case that scentless mayweed is little more than an attractive, but troublesome, weed.