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Imidacloprid (Bayer Advanced Fruit, Citrus, and Vegetable Insect Control) applied to the ground at the base of citrus trees provides the longest period of control, 1 to 3 months. Imidacloprid should only be applied once a year. Imidacloprid applications should be timed to protect periods of leaf flushing, such as in the spring and fall. Imidacloprid takes 1 to 2 weeks to move from the roots to the leaves, so it should be applied as soon as new flush begins to appear. To protect bees, avoid applying imidacloprid during the period 1 month prior to or during bloom. Removing blossoms before they open on young trees will prevent honey bee exposure to imidacloprid in the nectar/pollen.