In biblical times in Israel, olive trees were harvested by beating the branches with a stick, causing the olives to fall to the ground, as it says in our verse “when you beat thy olive trees”. According to the Sages, this hints to the blessing of abundance in the Land of Israel. There will be so much produce that the farmers will only need to harvest what falls off with the beating of the tree branches; they will not need to bother to climb a ladder in order to reach what was left at the top. What remains on the tree is left for the poor and needy. Now you can plant your roots in the blessed Holy Land!