CDFA Pest Prevention Plant Regulation Practice Exam

Which characteristic is commonly associated with secondary noxious weeds?

1. Short life cycle

2. Limited spread

3. Frequent establishment

4. Low reproductive output

The correct answer is: Frequent establishment

Secondary noxious weeds are typically characterized by their ability to frequently establish themselves in a variety of habitats. This frequent establishment can occur in disturbed areas, crop fields, and other environments where soil has been disrupted, making them common competitors with desired plant species. Their resilience and adaptability allow them to thrive under varying conditions, especially where primary plants may be stressed or absent. Choosing frequent establishment highlights the dynamic nature of these weeds in ecosystems, as they can quickly take advantage of openings provided by natural or human-induced disturbances. This characteristic is important for understanding how secondary noxious weeds can impact agricultural productivity and biodiversity. In contrast, a short life cycle might imply they are annuals that could complete their life quickly, but that does not encompass their broader establishment patterns across seasons. Limited spread suggests a constricted ability to disseminate, which does not accurately reflect the often invasive nature of these plants. Low reproductive output indicates a lack of prolific reproduction, which contradicts their frequent establishment and the impact they can have as they populate areas rapidly. Thus, frequent establishment is the best choice to describe secondary noxious weeds effectively.