The early growth conditions of seven kinds of broad-leaved trees including Castanopsis hystrix of Gaozhou were investigated in Gaozhou city in August 2014. The present results showed that Castanopsis hystrix had rapid height growth, followed by Acacia confuse Merr, and early height growth of Cinnamomum camphora was slower with three forest age (4 years, 3 years and 2 years old). Diameter growth of Castanopsis hystrix, Liquidambr formosana Hance, Rhodoleia championii were faster, while early diameter growth of Cinnamomum camphora was slower. Analysis of variance showed the tree height of the same species in 4 years and 3 years old were no significant differences (P>0.05), and showed trees high growth of seven kinds of broad-leaved trees including Castanopsis hystrix was not obvious from three-year to four-year-old, but trees high growth of seven kinds of broad-leaved trees with three-year-old and four-year-old was significantly higher than that of the 2-year-old (P<0.05). Except for Liquidambr formosana Hance, Rhodoleia championii, Acacia confuse Merr, diameter growth of the rest species were significantly different (P<0.05). The mean ratio of downhill and uphill with tree height in three forest age were 1.43 (4 years old), 1.48 (3 years old) and 1.24 (2 years old), and diameter downhill / uphill mean were 1.21 (4 years old), 1.32 (3 years old) and 1.32 (2 years old), growth condition of broadleaf species in downhill was significantly higher than those of the uphill. The study provided scientific reference for the species selection and sustainable management.
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