The study looked at how adding straw to soil in Northeast China affects moisture levels and crop growth. They tested different amounts of straw and when to add it. Results showed that adding 0.8 kg/m2 of straw at the three-leaf stage helped soil hold more moisture and reduced water use. This led to higher crop yield and water efficiency. Adding more straw didn't always mean better results. Overall, adding 0.8 kg/m2 of straw at the three-leaf stage was the best for soil moisture and water use efficiency.