In a protected wetland the number of native reed grass has decreased. They are being taken over by a non-native weed called purple loosestrife. A biologist decides to pull the purple loosestrife from the protected wetland. She predicts that as the number of purple loosestrife decreases, the number of reed grass will increase, improving the habitat. The results are shown in the graph. Compare the results shown in the graph with the prediction made by the biologist. Explain why the biologist’s prediction should be accepted or rejected.