Q. There are different traditions as to what bracha you make on papaya, what is Rav Millers opinion?

A. The Papaya looks like a tree, it may grow ten feet tall or more, lasts for several years and produces an annual crop like a tree and has all the qualifications of a tree as determined by Chazal. However it lacks some key botanical features of a tree and exhibits properties of a “Yerek”.  It bears closer similarity in many ways to a very tall stalk, since unlike a tree its stem is completely hollow on the inside and it does not usually produce branches. Its leaves and fruits grow directly on the top of the main stem, and it usually produces fruit during the first year, unlike most trees.
Since the papaya has some tree-like features and some vegetable-like features, Poskim disagree as to what is the proper brocho to be recited. Most Poskim follow Rav Pe’alim (O.H. 2: 30,) rule that papaya is not a tree and that the appropriate bracha is ha’adama. So does the Ridvaz (3: 531,) Kaf HaChaim (203: 13),Yechaveh Daas (4:52), Mekor HaBerachah, VeTein Berachah, (p.395,) Teshuvos VeHanhagos (3: 333) and Pischei Halacha. They offer different arguments or do so out doubt which is the correct brocho.
Other Poskim (Shevet Halevi 6: 165, Mishpetei Aretz, p. 27, Miperi Haaretz – quoting Horav Elyashiv zt”l) maintain that the brocho is haetz, so does too the OU website.
Horav Shlomo Miller’s Shlit’a opinion concurs with the majorities view of reciting ha’adama, since we are stringent on doubtful brochos.

Rabbi A. Bartfeld as revised by Horav Shlomo Miller Shlit’a