Effect of sunlight on Maple Tree's

This experiment was done over two days at York University's Grasslands and Woodlots. On the first day, researcher's went to the Grassland's and found 20 Maple tree's. There were tree's found on the edge of the Grassland's and some near the middle area. After numbering 20 Maple tree's the researchers measured the distance from 1 of the 20 tree's to three of the closest tree's found near the Maple. This was done using a trasect tape. So the researcher would take the tape and put it on the edge of 1 Maple tree and measure the distance to the edge of any tree close to it. This was done for a total of 3 tree's that were closest to the original Maple tree. Next the researcher plucked off 3 leaves from the original Maple tree and measured its length using a centimeter ruler. The measurement was taken from the top of the leaf to just before the stem (so stem not incuded). Then the researcher had to calculate the percent open space by making a rectangle shape with his/her hand and putting it above the original tree to estimate how much light could be seen. This value was a percentage, so the researcher madean estimation. This whole procedure was done for a total of 20 seperate tree's so for the second, third, fourth...until the twentieth tree the researcher calculated the distance to 3 tree's, the leaf length and open space. On the second day the exact same procedure was done on 20 Maple tree's in the Woodlots.