The study looked at how using reflective mulch under apple trees affects the amount of sunlight reaching the trees and the quality of the fruit. They found that the mulch increased reflected light under the trees, which improved the red color of some apple varieties. However, the mulch did not affect the quantity or weight of the apples. Overall, the reflective mulch helped enhance the color of the apples in the lower part of the tree canopy, but did not have a significant impact on other fruit quality factors like fruit firmness or bud setting.