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I found the virtual forest tutorial quite interesting. The results were not at all what I expected they would be. The technique with the fastest estimated sampling time was the systematic but I was surprised to see how close all three techniques were. For the two most common species the sampling technique with the lowest percentage of error was the systematic and the highest percentage was the random technique. For the rarest species, the lowest percentage was the random technique and the highest was the systematic. When comparing the three strategy results I noticed that the systematic samples had not picked up any Striped Maple at all. It would seem that the systemic technique may not be the most accurate for the rarer species as it is possible to miss species populations completely. It also makes sense that the systematic system worked so well for the common species. My percentage of error for Sweet Birch was only 1.3%. The species that are common would likely be spread throughout the area being sampled. They would also be present in higher numbers making it more likely that the population will be represented accurately in the samples collected. The systematic technique is not as accurate for rarer species and the random technique was overall the most accurate although not by as much as I had thought prior to this exercise. I think having more sample locations would have increased the accuracy of all the results but especially the results from the less common species. It is too easy to miss the small populations when using small numbers of samples.
I think that your project to examine the presence of green colour on aspen trees is pretty interesting. Your hypothesis, that the green colour would be present only on the south side of the tree trunk, was clear and well articulated and is also clearly falsifiable. It appears to be a strong hypothesis, if you are able to effectively measure the green colour. You explained well that the presence of this green colour would be an indication that the aspen trees would still be able to photosynthesize. The response variable that you mention, which is the presence of green colouring on the trunk of the aspens, is clearly stated. As well you did plainly explain how the experiment response variable would be categorical and the explanatory variable is continuous. The hypothesis and testing procedures all seem straight forward and feasible.