1907
In North America , these include the shoots of woodsorrel ( usually eaten along with the leaves ) , chickweeds , galinsoga , common purslane , Japanese knotweed , winter cress and other wild mustards , thistles ( de-thorned ) , stinging nettles ( cooked ) , bellworts , violets , amaranth and slippery elm , among many others .
 North America
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
 North America