Do individual-tree growth models correctly represent height:diameter ratios of Norway spruce and Scots pine?

▶ We examined four individual tree models in Europe: BWIN, Moses, Silva and Prognaus. ▶ We simulated growth of open-grown trees and on research plots for 15 or 30 years. ▶ Height:diameter ratios were correctly predicted by all four models. ▶ Height:diameter ratios were within the bounds of open grown trees and dense stands. ▶ They decreased with age and density; dominant trees had lower ratios than mean trees.