I am conducting a research to see the relationship between soil properties and wild ungulate browsing intensity on the tree saplings in the natural forest. I have analyzed soil data for some chemical properties. Since, the relationship between ungulate browsing intensity index and soil property can not be directly established, I wanted to calculate the vitality index. I have the structural parameters of the tree saplings such as sapling height, basal diameter, shoot diameter at the herbivore damaged point, crown length, crown height, and crown width for 6 tree species. But, I faced a challenge how to calculate the vitality index based on these parameters. If any body knows this please share with me. Thank you.