Thinning Taiwania plantations in Southern Taiwan had different effects on growth and structure. Heavy thinning didn't increase basal area and volume as much as medium thinning, but it did boost growth rate. Thinning changed the way trees were spaced out, making them more random or clumped. The difference in tree sizes in the plantation decreased after thinning, with more trees having similar sizes. Competition among trees affected growth variations, leading to changes in the proportions of trees with different size differences.