USE OF TREGRO TO SIMULATE THE EFFECTS OF OZONE ON THE GROWTH OF RED SPRUCE SEEDLINGS

TREGRO, a model developed to simulate the growth of sapling red spruce (Picea rubens Sarg.), was parameterized to grow 2- to 3-yr-old seedli ngs. Results of the simulation compared favorably to actual growth of seedlings used in a field study of the effects of ozone and acidic pre cipitation on tree physiology and development. Furthermore, a 10-yr si mulation produced a modeled tree that corresponded to saplings used in another field experiment. Additional simulations were conducted to co mpare predicted effects of ozone on seedling growth to those measured in controlled experiments. Based on the performance of the model, we b elieve TREGRO can be used effectively to simulate both seedling and sa pling red spruce growth, and the potential effects of ozone on the dev elopment of the trees.