What is the "white poplar" you found?
Original meaning: wood name, cypress, also known as "cypress"
A general term for the genus Cupressus.
So you can find "white poplar".
But Mr. Bai Yang is a pseudonym, not a fixed phrase, so I can't find "Bai Yang", but Mr. Bai Yang's "Bo" should be pronounced "Bo".
For example: Zhang Baizhi.