Shepherd's purse is considered a weed on farms in North America. It is an annual or biannual that do well on disturbed soils, especially fertile soils. One plant can produce tens thousands tiny seeds in summer. More information can be found on Wikipedia, [WIKI]http://en.wikipedia.org/wiki/Capsella_bursa-pastoris[/WIKI] Shepherd's purse is a crucifer. It is considered a delicacy in China. There is even commercial growing of it in China. On medical side, shepherd's purse can stop bleeding. It could also reduce breast milk production. Therefore pregnant and lactating mothers should minimize the exposure. Same goes for people with cardiovascular problems such as thick blood. I have gathered seeds from one plant and sowed lots of them in my overwinter patch. Hopefully next spring I can enjoy some fresh Shepherd's purse.