Illinois Pesticide Applicator Practice Test

What is the life cycle characteristic of a biennial weed?

1. Seeds in the first summer

2. Seed the second summer and die in the winter

3. Lives for one season

4. Remains dormant for several years

The correct answer is: Seed the second summer and die in the winter

A biennial weed is characterized by a life cycle that spans two years. In the first year, the plant typically germinates and grows primarily as a rosette of leaves, storing energy for the second year. During the second summer, the biennial weed will flower, produce seeds, and then die off, often in the winter. This two-year life cycle allows biennial weeds to bridge seasonal changes effectively, making them a common challenge in weed management. The process of germination in the first year and seeding in the second summer aligns with the characteristics of biennial plants, distinguishing them from annuals, which complete their life cycles in one year, and perennials, which can live for multiple years and do not necessarily die off after seeding. This understanding is critical for effective weed control strategies, as it informs the timing and methods of application for herbicides or cultural practices.