SOLVED. Middle Grade Fantasy series about a some kids who live in the roots of a tree and some who live in its branches. [s]

[Amy]

I read it in jr. high in the 80s. But It may have been published in the 60s or 70s. I know there were at least 2 books in the series and maybe 3. The first book was about the people who lived under the tree and the 2nd was about the kids who live in the branches. I think the 3rd was about when the protagonists of the first 2 books met. There were no humans in the series. I remember picturing the kids at mon-chi-chis (it was the 80s ¯\_(ツ)_/¯). I Also remember thinking the author was a Russian woman and that her first or last name started with an “O”. I know it’s not the Borrowers, Minipins, or the Enid Blyton books.

[Ann]

Possibly the Green Sky Trilogy by Zilpha Keatley Snyder? The first book in the series is Below the Root

[Amelia]

I think it might be Toby Alone

[Amy]

I think it is the Green Sky Trilogy. That’s amazing! Thank you!