The amount of nitrogen given to apple trees affects how many fruits they produce and how big those fruits are. More nitrogen can make the fruits larger, but it can also make them less firm, less colorful, and have less dry matter. This means the fruits might not be as valuable to sell. The shape of the fruits can also change, becoming flatter with more nitrogen. The density of the leaves on the tree can also affect the quality of the fruits, with denser canopies leading to less firmness and dry matter in the fruits. The relationship between canopy density and fruit mass is more complicated, following a curved pattern.