The Selection of Grey Models for Some Tree Species in Seedling Stage

The seedling dynamic procedures of growth of some tree species, such as Pinus massoniana, P. elliottii, P. taeda, Camellia oleifera, Aleurites montana,A.fordii have been modeled with grey model and Stype curve model. The results show that there are different dynamic models of growth in the seedling stage of different tree species. GM(1,1) and S type curve models have broad adaptability in modeling growth of trees in seedling stage. There are different results for height growth of different tree species when using GM(1,1) and S type curve models. GM(1,1) model is preferable to S type curve model in the modeling for the thick growth near ground. GM(2,1) and GM(1,N) can been used unwillingly for modeling some tree species. The modeling results by using Verhulst model are the worst of seedling modeling for all tree species with grey model and S type curve model.