Service tree (Sorbus domestica).
From Wikipedia:
“The fruit is a component of a cider-like drink which is still made in parts of Europe. Picked straight off the tree, it is highly astringent and gritty; however, when left to blet (over-ripen) it sweetens and becomes pleasant to eat.
The sorb tree is cited in the Babylonian Talmud Tractate Ketubot page 79a. The case involves purchasing an Abba Zardasa, which is translated by Rashi, an early Medieval scholar as a forest of trees call Zardasa that is used for lumber because the fruit is not commercially important. The Aramaic word zardasa may be the origin of the English sorb.”
Westmount Overlooked 