Matricaria discoidea, commonly known as pineappleweed, wild chamomile, and disc mayweed is an annual plant native to North America and Northeast Asia but which has become a cosmopolitan weed. It is in the family Asteraceae. The flowers exude a chamomile/pineapple aroma when crushed. They are edible and have been used in salads (although they may become bitter by the time the plant blooms) and to make herbal tea. Pineapple weed has been used for medicinal purpose (Wikipedia)