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Herbivory is among the most influential disturbances shaping the evolution and function of terrestrial plants. Herbivory by large ungulate herbivores can impact forest regeneration, but their long-term impacts on tree function and growth are less studied. Two separate exclosure experiments established at different time points (1989 and 2012) were used to examine how ungulate herbivory affects primary metabolism and defense chemistry expression of leaves and sapling growth rates over time. During the three year period in the first experiment, approximately 60% of aspen stems in unfenced plots showed evidence of being browsed by ungulates resulting in leaves that were only half as large, and aspen stems that were half as tall as aspen inside of fenced plots. �Regenerating aspen exposed to browsing over the three-year period had 33% lower foliar starch concentrations and a nearly two-fold induction of condensed tannins compared to aspen protected from browsing. In the second experiment, aspen exposed to ungulate herbivory over a 26 year period maintained smaller leaves, had lower annual radial growth rates and were still shorter than the critical recruitment threshold of 2 meters required to escape ungulate herbivory. In contrast, average heights of aspen protected from ungulates was approaching 6 meters. Leaves browsed over the 26 year period had 53% lower starch concentrations and greater expression of condensed tannins (35%) and phenolic glycosides (50%) than protected leaves. �We found no evidence in either experiment that ungulate browsing negatively impacted photosynthesis of leaves on browsed plants. It appears that increased investment in chemical defense, lower nonstructural carbohydrate concentrations and loss of leaf area, slows radial and recruitment potential of regenerating aspen.