This Summer Dichotomous key identifies species based on their distinct scientific names. Summer Dichotomous key is very useful because it directs non-expert users to look at known, important organisms to identify organisms. Many people may not be able to tell different species of pine trees apart based on the arrangement of needles on a branch, for example. Still, the key would be able to ask them that question and provide them with useful information based on the answer. As the name implies, a dichotomous key arrives at the response to species identification by presenting a series of questions with two possible solutions.