本文是根据几年来的试验及调查结果,结合1956年在华北四省范围内,联合各所、站、场等进行的播种期试验的初步总结,就华北地区提早播种问题进行阐述和讨论,以供生产上的参考。限于研究年代短,资料不足,只能作为进一步深入解决这一问题的一个开端。 This article is based on the results of several years of experiments and surveys, combined with a preliminary summary of the sowing experiments conducted in 1956 in the four provinces of North China in conjunction with various stations, stations and farms to explain and discuss the issue of early sowing in North China for Production reference. Limited to the short research age and lack of information, it can only serve as a beginning to further solve this problem.