What each of the four species is actually doing as a plant, set against what the sugya asks of it. Grafting versus cross-breeding versus cross-pollination in the esrog and what DNA can and cannot see; why the pitom stays or falls; what makes a Deri lulav a Deri; how rare a truly three-leaved myrtle is and why; the willow's field key; a blemish guide that reads black dots, brown scars, chazazis and scratches region by region; and the esrog lineages, orchard by orchard, with what was claimed against each and who relied on it.