Authorities in Shandong have released technical guidance aimed at improving the fertility of grain fields. The document, formulated jointly by the Shandong Agricultural Technology Extension Center, the Chinese Academy of Agricultural Sciences' Institute of Environment and Sustainable Development in Agriculture, and Shandong Agricultural University, provides a comprehensive set of recommendations to protect and enhance cultivated land quality, promote the sustainable use of farmland resources, and strengthen the foundation of the region's grain production capacity.

This practical and technology-infused guidance centers on five key principles: increasing organic matter, returning crop residues, applying inputs precisely, improving tillage methods, and promoting green practices. It essentially prescribes a tailored "nutritional plan" for the province's cropland.

While the old saying goes that "crops rely on manure," modern farming now emphasizes not just chemical fertilizers but also the use of organic amendments to nourish the soil. The guidance explicitly calls for a significant increase in the application of organic fertilizers and the implementation of crop stubble return.

For farmers, the most pressing questions are often "how to apply" and "how much to apply." The guidance offers a tiered recommendation. For plots with relatively low soil organic matter content (below 15g/kg), it suggests applying 400 to 500 kilograms of commercial organic fertilizer or 1,000 to 1,200 kilograms of well-composted manure per mu. For medium-fertility land, the recommended application rate is reduced to 300 to 400 kilograms of commercial organic fertilizer.

Furthermore, the guidance encourages the direct return of crushed corn and wheat stalks to the fields. This practice, when combined with the application of decomposition-promoting microbial agents and a small amount of urea, allows the stalks to decompose rapidly into a natural fertilizer. This approach not only improves soil compaction but also achieves a green cycle of nutrients.

Long-term rotary tillage can easily lead to the formation of a hard "plow pan," which prevents crop roots from penetrating deeply and reduces the soil's ability to retain water and nutrients. The guidance advocates for improving tillage methods by conducting deep plowing or subsoiling every 2 to 4 years, reaching a depth of 25 to 40 centimeters. This is likened to giving compacted soil a "deep tissue massage," allowing the farmland to "breathe" again.