Next came cane holing, the backbreaking job of digging precisely measured holes and building ridges around them from scooped-out soil. Then pairs of slaves inserted three cane tops into each hole and packed it with manure, seaweed, or sludge before covering it with earth. As the planted cane grew, the slaves reinforced the ridges, weeded the thousands of rows between the cane holes, removed dry stalks, and pruned. Many plantations staggered their planting schedules so that slaves finished the dreaded job of cane holing in one field only to repeat it in another. See sugarcane agriculture.