In 1997, the Pinus massoniana monoculture forest was planted, with a density of 2,505 plants / ha , on which the tending management was carried out for three consecutive years after afforestation. In the 7th year, the released thinning was carried out, with the number of the thinned trees accounting for 20% -30%; in the 11th year, the first intermediate cutting was carried out, with the number of the cut trees ranging from 30% to 40%; in the 16th year, the second intermediate cutting was carried out, through which the interference trees were removed and proper thinning was conducted for the selected 90-120 target trees per ha, so as to retain the density of 450~525 plants / ha. At the same time, 120 forest gaps with a diameter of 6m were cut out and reserved for planting trees per acre were cut out for planting Castanopsis hystrix. In 2014, clumps of Castanopsis hystrix were planted in the gap, with a density of 120 clumps / ha. The 2-year-old container seedlings were selected. Block tending was carried out for 2 to 3 years after clump planting of Castanopsis hystrix, and Massoniana Pinus was tended individually, with timely removal of its interference trees. In the 15th year or so, one target tree was selected from each Castanopsis hystrix cluster, and its interference trees were removed every 5 years. When Massoniana Pinus reaches the target DBH, it would be selectively cut for use, and the target tree of Castanopsis hystrix will be tended individually afterwards.
The close-to-nature transformation by replanting the rare broad-leaved tree species of Castanopsis hystrix in clumps in the gaps between Massoniana Pinus plantations is beneficial to the formation of excellent stem form of Castanopsis hystrix and has wide applicability for Guangxi state-owned forest farms and forest farmers. (Experimental Center of Tropical Forestry)
Clump planting of Castanopsis hystrix under Massoniana Pinus plantations
Clump planting and interplanting under Massoniana Pinus plantations