Ornamental and Turf Pesticide Applicators Practice Exam

What is a key characteristic of biennial weeds?

1. They grow for a full year before flowering

2. They can die after one season

3. They form a rosette of leaves the first year

4. They reproduce throughout the year

The correct answer is: They form a rosette of leaves the first year

A key characteristic of biennial weeds is that they form a rosette of leaves the first year. Biennial weeds typically have a two-year life cycle. In the first year, they concentrate on vegetative growth, developing a rosette of leaves close to the ground, which helps in water and nutrient absorption while protecting themselves from environmental extremes. This rosette is crucial for the plant's survival through the winter months. In the second year, these weeds will use the energy stored during the first year to flower, produce seeds, and then die off after fulfilling their reproductive phase. Understanding this growth habit is essential for managing biennial weeds effectively, as control methods can be timed to target them before they mature and produce seeds. The other characteristics outlined in the options do not accurately capture this unique life cycle and growth pattern characteristic of biennial species.