Historical clue formulations

• State trees of North Dakota — 2025-09-17
• Trees on the National Mall — 2025-09-14
• Targets for bark beetles — 2025-08-30
• Stately trees — 2025-07-20
• Symbols of wisdom — 2025-01-01
• State trees of Massachusetts — 2024-09-24
• Shade providers at the National Mall — 2024-02-02
• Stately trees — 2024-01-30
• Stately trees — 2023-10-02
• They form parallel lines along the National Mall — 2023-07-15
• Majestic trees — 2023-05-15
• Stately trees — 2023-01-31
• Trees that canopy Central Park's Literary Walk — 2022-08-27
• Eugene O'Neill's "Desire Under the ___" — 2022-08-19
• Plantings lining the Literary Walk in Central Park — 2022-01-02
• Massachusetts' College of Our Lady of the ___ — 2021-09-19
• Eugene O'Neill's "Desire Under the ___" — 2021-04-18
• Classic boulevard liners — 2021-03-10
• California : palms :: New England : ___ — 2021-02-11
• Stately street liners — 2020-11-08
• Symbols of hope during the American and French Revolutions — 2020-09-19
• The Liberty Tree and others — 2020-09-18
• Colonnade trees — 2020-07-23
• Blighted trees — 2020-06-08
• Trees that line the National Mall — 2020-04-12
• Things that suffered a 20th-century blight — 2020-03-09
• Eugene O'Neill's "Desire Under the ___" — 2020-03-06
• Newport, R.I., estate that's a National Historic Landmark, with "the" — 2019-03-02
• National Mall liners — 2018-08-18
• Classic street liners — 2018-06-19
• Trees attacked by bark beetles — 2018-04-23
• Majestic trees — 2017-12-06
• Stately shade trees — 2017-07-17
• Stately hardwoods — 2015-11-30
• State symbols of Massachusetts and North Dakota — 2015-04-27
• Massachusetts' College of Our Lady of the ___ — 2015-01-22
• State trees of North Dakota and Massachusetts — 2014-09-01
• Shapely shade trees — 2014-07-14
• Frequent features of John Constable landscapes — 2014-07-13
• O'Neill's "Desire Under the ___" — 2014-06-23
• Street-lining trees — 2014-06-02
• Stately shaders — 2014-03-10
• Chinese ___ (popular bonsai trees) — 2013-08-09
• Classic trees on shady streets — 2013-06-24
• Group in many a park — 2012-07-29
• O'Neill title trees — 2012-07-24
• Trees in Gray's country churchyard — 2012-02-24
• State symbols of North Dakota and Massachusetts — 2011-07-24
• Part of the New Haven landscape — 2011-02-10
• Shady group? — 2010-12-03