Analysis of Growth Effect on Cunninghamia lanceolata interplanted with Different Specifications Container Seedlings of Phoebe bournei （Hemsl.）Yang

The experimental forest of Cunninghamia lanceolata interplanted with six specifications container seedlings of Phoebe bournei as the research object, the dynamic tracking of 1～8 years after afforestation was carried out, the ground diameter, DBH,maximum crown width, tree height, branch height of P.bournei（Hemsl.） and C.lanceolata,and individual volume of C.lanceolata were analyzed.The results showed that the ground diameter, maximum crown width and tree height of container seedlings gradeⅠwere higher than the same age seedlings gradeⅡof C.lanceolata interplanted with different specifications container seedlings of P.bournei in afforestation year, 2 years and 8 years after afforestation.The ground diameter, DBH,maximum crown width, tree height, branch height in December 2016,April 2018 and February 2024 and the corresponding growth of 7 years and 2 months of 3-year-old grade I seedlings were the largest, and the average annual growth was 7.16 mm, 7.40 mm, 35.19 cm, 63.20 cm and 10.66 cm, respectively.After 8 years of afforestation, the ground diameter, DBH and individual volume of C.lanceolata in the afforestation land of 1-year-old II container seedlings were the largest, reaching 44.04 cm, 36.53 cm and 0.92 m³,respectively, which were 11.38 %,10.83 % and 21.05 % higher than the average.The maximum crown width and tree height of C.lanceolata in the 2-year-old II container seedling afforestation land were the largest, reaching 6.86 m and 21.53 m, respectively, which were 10.47% and 3.66% higher than the average.Based on the analysis of each index of P.bournei and C.lanceolata,the average comprehensive score of C.lanceolata interplanted with 3-year-old grade I seedlings of P.bournei was the highest, reaching 0.7347.In order to promote the young P.bournei growth of C.lanceolata interplanted with P.bournei and take into account the cultivation of large-diameter timber of C.lanceolate,it was suggested that using C.lanceolata interplanted with 3-year-old grade I seedlings of P.bournei,whose afforestation effect is good.