Source for maple syrup

I believe the answer is:

sap

(Other definitions for sap that I've seen before include "Cosh; plant's juice" , "Plant liquid or general vitality" , "Vital plant juice" , "Moisture in wood of a tree" , "Liquid that circulates in plants" .)

I've seen this clue in The New York Times.

Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.