WEED MIGRATION 769 



in the Mississippi valley. It was reported from Pottawattamie 

 county, Iowa, in 1909 and it was abundant in Salt Lake City, 

 Utah, in 1908 where it evidently had been naturalized for some 

 time. It was abundant in places in the Sacramento Valley in 1912 

 indicating naturalization for some time. Brewer and Watson in 

 Botany of California (1876) state "Sparingly naturalized." 



49 



