Left to nature, blueberry fields are an intermediate that eventually leads to forest land. Left unattended bushes and trees eventually destroy the blueberry plants. Periodic burning prevents this from happening. Burning also kills insects, fungi and disease germs. It also keeps the plants from growing tall. Tall plants produce less fruit and are more difficult to harvest. Burning is usually done every other year with harvesting taking place on the off years. Experiments are being carried out to reduce the frequency of burning using a process called flail mowing in which plants are cut mechanically.