Agronomy Degree Practice Exam

After an alfalfa field has outlived its productive life, what is the minimum recommended time before replanting alfalfa?

1. One year

2. Two years

3. Four years

4. Eight years

The correct answer is: One year

Replanting alfalfa after its productive life requires a careful consideration of several factors, including soil health, pest management, and crop rotation practices. The minimum recommended time before replanting alfalfa is one year. This period allows for the breakdown of any residual pathogens or pests that may have accumulated during the previous alfalfa crop's growth. A year’s gap can also enhance soil health by allowing for another crop to be grown, which can improve soil structure and nutrient availability, ultimately supporting a successful reestablishment of alfalfa. Incorporating a different crop during this time helps reduce the risk of diseases and pests that typically affect alfalfa, promoting a better growth environment for the subsequent alfalfa crop. A longer waiting period might not provide additional benefits and could instead delay the farmer's return on investment, making the one-year interval a practical and effective choice for replanting alfalfa.