Under what tree was the Buddha born? Sal or Asoka tree?

I do some web-searches about the Ashoka and Sal (Sala) trees in connection with the Buddha’s birth place. It becomes confused whether the Buddha’s mother (Queen Māyā of Sakya) gave birth to the Buddha while grasping the branch of a Sal tree or an Ashoka tree (in a garden in Lumbini in south Nepal, while en route to her grandfather’s kingdom)?

Does anyone know for sure the Buddha was born under the Ashoka tree or the Sal tree? Thanks.

I found the answer: The Buddha was born under the Asoka tree: See pp. 14-5
Forest and Trees Associated with the Load Buddha by Basanta Bidari.pdf (7.0 MB)
in Ancient Nepal Journal of the Department of Archaeology, number 139, June 1996, pp. 11-24

Cf. Sylvan Stroll: The Tree Associated with the Birth of Buddha