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越区种植（南种北种）主要指在玉米生态种植区域内，种植玉米的生育期超过当地的无霜期，造成玉米不能安全成熟的现象。近年来，东北地区把控制玉米越区种植作为调整种植业结构、提高玉米质量的重点工作来抓，积极采取行之有效的措施，取得了明显的成效。2001年东北3省玉米越区
Cross-cropping (South North Species) mainly refers to the phenomenon that the maize growing season exceeds the local frost-free period in maize ecologically-cultivated areas, causing the maize to fail to mature safely. In recent years, the northeastern region has taken effective measures to control the cross-planting of maize as a key task of adjusting the planting structure and improving the quality of maize and has achieved remarkable results. In 2001 the northeast 3 provinces of corn more area