Here the Hebrews are directed to cut and gather various types of greenery. This act symbolizes abundance and fertility. This accounts for the reason this feast is elsewhere called the feast of Harvest (Exodus 23:16; Exodus 34:22). These cuttings also have a practical purpose because the Hebrews are to make huts out of them in order to live in the booths for the seven days of the feast
40 And you shall take on the first day the fruit of splendid trees, branches of palm trees and boughs of leafy trees and willows of the brook, and you shall rejoice before the LORD your God seven days.