Best time to control winter annuals is?

• A. Seedling stage in fall or early spring
• B. In summer
• C. After maturity
• D. During flowering

Answer: (A)

Target winter annuals when they are still seedlings in fall or at the very start of spring. These weeds germinate in fall, overwinter as small rosettes, and complete their life cycle in spring. At the seedling stage they are small, actively growing, and have tender tissue that herbicides can readily be absorbed and translocated to the growing points, so you get effective control with lower rates and less impact on nearby plants. Waiting until summer often finds these weeds dormant or past their most vulnerable growth stage; after maturity they’re tougher to kill, may have stored energy reserves, and are set to produce seeds, which keeps the seed bank alive. During flowering, the plants are focus­ing energy on reproduction, which also reduces herbicide effectiveness and increases the chance of seed production before control. Controlling at the seedling stage minimizes future problems by preventing seed production and reduces weed pressure in the stand.