This study investigated the effects of different straw mulching methods (surface coverage and deep burial) combined with varying nitrogen (N) fertilization levels on the root distribution, nitrogen utilization efficiency, and yield of summer maize. Deeply buried straw significantly promoted deep root growth, while surface coverage improved root growth in the upper soil layers. The optimal treatment was deeply buried straw combined with medium N fertilization, which increased deep root length density, N use efficiency, and yield.
