Study on Fertilization Technology of Fast-growing and High-yielding Poplar Plantation Ⅱ. After Manuring Experiment

Several experiments of after manuring with N,P,K compound fertilizers and urea in different ratio,amount,and application patterns were conducted.The results showed that after manuring had greater effects on the increment of dbh than on height increment.The best application pattern could double the increment.The effects of different fertilizer followed the order of ureafertilizer 3fertilizer 2fertilizer 1.The results of after manuring on 2-year-old poplar plantation showed an increased absolute value of increment,the variation of increment after manuring was smaller than that on current planted plantations.The difference among fertilizer followed the order of fertilizer 2fertilizer 1ureafertilizer 3.As for application pattern,separately application was better than that of one-time applying.The experiment showed that middle June was the best time for fertilizing.