 In those cases, nothing but cellulose, nothing but wood. There's no protein involved. There's no green tissue. There's no buds. There's no cambium. There's no living material. That's why ground-up tree trimmings are such a great mulch because you have the balance, the combination, carbon to nitrogen balance of the protein, the green stuff, and the carbon, the brown stuff, and the cellulose and the wood.