The study looked at how different types of grass planted between rows of apple trees affected soil in a 1-year-old orchard. They found that the grasses decreased soil temperature in summer, increased soil water content, organic matter, and nitrogen and phosphorus levels, and lowered soil pH. The effects varied depending on the grass type and soil depth. Dichondra repens was the most effective at improving soil fertility, while Cynodon dactylon and Festuca arundinacea had the least impact. Overall, the type of grass planted was crucial in determining how well the soil was enriched.