Growth Responses of Mixed Young Forests of Toona ciliata and Cunninghamia lanceolata to Different Fertilization Measures

The effects of different fertilizer types and amounts on the growth of young mixed forests of Toona ciliata and Cunninghamia lanceolata were investigated by fertilization experiments of Pushang State-owned Forest Farm of Shunchang，Nanping in 2020 and 2021，the results were as followes：the ground diameter，tree height，and annual height of the fertilized stand were increased by 26. 18%，7. 25% and 62. 5% compared to the control value respectively at the first year，and 12. 83%，19. 62% and 28. 09% at the second year. As a whole，the ground diameter，tree height，and annual height of the young mixed forests showed an increasing trend with the increase of fertilizer amount. With regard to the effects of the different fertilization type，the effect of different fertilizer type on the growth of forests were mixed fertilizer>compound fertilizer>organic fertilizer. In the first year,the ground diameter show very significant differences among repetitions，treatments and interaction between repetition and treatment，tree height show very significant differences among repetitions and not differences among treatments，and annual height show very significant differences among repetitions and treatments. In the second year,the ground diameter and annual heigh show significant differences among treatments，tree height show very significant differences among treatments and not differences among repetition. And it was found that the growth performance of ground diameter was mostly impacted by fertilization after two years experiments，and the mixed fertilizer with a fertilization rate of 150g per plant was the best for young mixed forests of Toona ciliata and Cunninghamia lanceolata.