Historical clue formulations

• Argentine grassland — 2017-08-22
• Patagonian plains — 2012-03-13
• Argentine grassland — 2007-05-07
• Grassy Argentine plains — 2004-12-13
• Argentine plains — 2002-07-16
• Argentine grassland — 2001-02-25
• Argentine area — 1999-06-12
• Gauchos roam these — 1995-07-26
• Patagonian plains — 1995-02-22
• Argentine grasslands — 1994-11-29
• Gaucho's home — 1994-01-23