Assembled & edited by Keeper Trout It is important to understand that all alkaloid concentrations can be highly variable. This can be the result of many factors. Genetics, environment, age, part sampled, weather, health, time of year or time of day, and whether the plants were wild or cultivated, have all been noted as factors potentially capable of influencing the alkaloid content and/or composition in plants. Substantial variations can be encountered based on the variety, local form, age, growth stage and other factors. Cacti can sometimes be highly variable in appearances. This work attempts to present multiple images of single species in habitat and grown under different situations or in multiple hands whenever possible. One clear advantage to this being a PDF is the elimination of concerns about minimizing cost through limiting the number of color photos that are included.