Historical clue formulations

• Betel nut-yielding tree — 2015-09-30
• Tropical palm — 2015-04-02
• Betel palm — 2005-12-09
• Tropical palm — 2005-09-07
• Tropical palm — 2005-03-17
• Betel palm — 2005-01-07
• Betel palm — 2000-06-14
• Asian palm — 2000-02-13
• Betel nut tree — 1999-08-22
• Betel palm — 1999-08-21
• Betel palm — 1999-03-30
• Tropical Asian palm — 1998-12-06
• Betel palm — 1998-11-07
• Betel nut source — 1998-09-05
• Asian palm — 1997-05-01
• Tropical palm — 1997-01-12
• Betel palm — 1996-12-08
• Tropical palm — 1995-01-22