华北落叶松在一年之内生长期较长,一般从四月初萌发,八月下旬封顶,究竟什么时候追肥效果最好呢?习惯上在七月份追肥,但通过我们在神池县义井林场对苗木生长过程的观测和追肥试验,得到不同的结论,现将试验结果报告如下:一、观测试验地条件观测试验地设在神池县义井林场苗圃。海拔1470m,年均气温4。8℃,多年平均降雨肠omm。土壤为黄绵土,土壤有机质含 Larix principis-rupprechtii grows longer within a year, generally germinating from early April and capping in late August. When is it best to apply the fertilizer? It is customary to top-dressing in July. However, Seedling growth process observation and top dressing test, get different conclusions, the test results are reported as follows: First, the observation and observation of the conditions of the experimental site is located in Shenchi County Yijing farm nursery. 1470m above sea level, with an average annual temperature of 4.8 ℃, many years of average rainfall omom. Soil is loamy soil, soil organic matter