I'm in engineering and physics and I don't have to present very often. I'm currently in my junior year and I've only had to present a couple times. For one presentation, I talked to my professor and asked to do it during her office hours. For the other presentations, the classes were small and I felt comfortable stutterering. If you have a passion for forestry, biology, or any of the sciences, you absolutely need to go to college and get your degree.