There are a number of relatives of this plant that cause similar problems.  It is known to be a problem in prairie areas in Illinois and DNR has issued a document on it.  I have seen it and there are warnings for it at the McHenry County Conservation District parks.

http://dnr.state.il.us/INPC/pdf/VMG%20Wild%20parsnip%20revised%202007.pdf

There is also a scary relative that I have seen out in the Eastern states, known as "giant hogweed," that has been a problem there.  Imagine a gigantic wild parsnip that can reach 15 feet and extend 3 feet in all directions from the center stalk.  These were reported in Illinois last year and the state has been developing a plan to deal with the threat.  

http://www.landscapeonline.com/research/article/7708

Erik

----- Original Message ----- 
  From: Brian Fredericksen 
  To: [log in to unmask] 
  Sent: Thursday, June 28, 2007 9:02 AM
  Subject: [BEE-L] wild parsnip


   invasive plant wild parsnip 
  http://www.wnrmag.com/stories/1999/jun99/parsnip.htm

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