News Plants Leonardo da Vinci’s rule for how trees branch was close, but wrong It’s the surface area, not the thickness, of a limb that determines how it branches The branching structure of virtually every leafy tree — such as this southern live oak in Charleston, S.C., dubbed the Angel Oak — is dictated by the surface area of its limbs, a new study finds. Michael Ver Sprill/iStock/Getty Images Plus Share this:EmailFacebookTwitterPinterestPocketRedditPrint By James R. Riordon April 27, 2022 at 8:00 am Leonardo da Vinci was wrong about trees.