Q: This task is about writing a correct answer for the reading comprehension task. Based on the information provided in a given passage, you should identify the shortest continuous text span from the passage that serves as an answer to the given question. Avoid answers that are incorrect or provides incomplete justification for the question.
Passage: Natives of North America began practicing farming approximately 4,000 years ago, late in the Archaic period of North American cultures. Technology had advanced to the point that pottery was becoming common and the small-scale felling of trees had become feasible. Concurrently, the Archaic Indians began using fire in a controlled manner. Intentional burning of vegetation was used to mimic the effects of natural fires that tended to clear forest understories. It made travel easier and facilitated the growth of herbs and berry-producing plants, which were important for both food and medicines. Question: What was the intentional burning of vegetation intended to mimic?
A:
effects of natural fires