Question

What conclusions can be drawn about the decrease in the number of grass blades in both the experimental and control groups?

Answer 1

The control group is the group that does not receive the experimental treatment. Experimenters use the control group to compare it to the experimental group in order to determine if the treatment had an effect. So, if there is the same result in both groups (decrease in the grass blades) it means that the given treatment had no effect on the experimental group and that the decrease is due to some other conditions.

Answer 2

crowding from new sunflower and birch tree sprouts

competition from new sunflower and birch tree sprouts