This Jan. 26, 2013 photo shows a a bar code attached to a marijuana plant at a grow house in Denver. The bar codes are assigned to each plant and follow it through the growing and distribution ... more 
This Jan. 26, 2013 photo shows a a bar code attached to a marijuana plant at a grow house in Denver. The bar codes are assigned to each plant and follow it through the growing and distribution process. Washington state is considering the use of a similar tracking system. (AP Photo/Ed Andrieski) less 
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Associated Press | Photo By Ed Andrieski
Tue, Jan 29, 2013 4:48 AM EST