According to a 1994 USDA document, "Imidacloprid is a systemic and contact insecticide exhibiting low mammalian toxicity, with primary activity on sucking insects...". What precautions, if any, should be taken when dealing with plants that have been treated with imidacloprid? I'm thinking of the case of ornamental plants that are edible and can potentially be consumed. For example, a containerized citrus tree. Are there any concerns with eating either existing or newly formed fruits?