Haphazard had the fastest sampling time while area systematic had the slowest.
Haphazard and random appeared to produce similar results, where the systematic found more abundance of the higher population species. I want to think systematic was more accurate as it found more consistently, both random and haphazard have so many variables in topography and choice of sampling area. The percentage of error found on the most common species was 7.1% for Red Maple and 11.8% for White Oak. For the least common species it seems to increase with less common species.
Accuracy should be higher where there are more species present. It would be hard to ensure proper and accurate numbers in species where there were so few you would have trouble counting and ensuring an accurate number.
Missing some details here, what were the actual sampling times as usually they are quite close. What about the error for rare species and what does the comparison tell you. This is a good assignment to spend some time on as it gives you a chance to see how different experimental designs play out virtually which can help with planning your own project.