Who knew that trees have only a limited set of "architectures"? Francis Hallé, Roelof Oldeman and P. B. Tomlinson observed as many as 23 (later revised to 24), each a different combinations of six options: 1) To branch or not to branch? 2) If branching, only at bottom of stem or all along it? 3) Do you grow without rest or is there a dormant season? 4) Do all your branches grow upward or outward, or do some grow upward and outward? 5) Do you flower at branch tips or on smaller lateral branches? 6) Do your branches change back and forth between growing upward and outward? Hallé, Oldeman and Tomlinson, Tropical Trees and Forests: An architectural analysis (1978), cited in William Bryant Logan, “The Things Trees Know,” Old Growth: The best writing about trees from Orion magazine (Northampton, MA: Orion, 2021), 25-38, 26f; image source