Where does “upflore” come from?

upflore (Old English) comes from Old English ūp-, from Old English ūp, from Proto-Germanic upp, from Proto-Germanic ub, from Proto-Indo-European upó, from Proto-Indo-European h₃ewp-.

Ancestry of “upflore”, step by step

Step	Language	Word	Meaning
1	Old English	ūp-	up-
2	Old English	ūp	up, from above
3	Proto-Germanic	upp	up, upwards
4	Proto-Germanic	ub	under
5	Proto-Indo-European	upó	under, below
6	Proto-Indo-European	h₃ewp-	—

Every word from Proto-Indo-European h₃ewp- →Every word from Proto-Indo-European upó →Every word from Proto-Germanic ub →