Arena, an insecticide from Arvesta Corporation (San Francisco, CA), has received federal registration. The active ingredient is clothianidin. Arena is formulated as a 0.5% granule and a 50% water-dispersible granule. This insecticide is labeled for control of grubs, chinch bugs, webworms, cutworms, and other insect pests of turfgrass. Arena works through contact and ingestion. In addition, it has systemic activity and has the same mode of action as imidacloprid (Merit). Both Arena and Merit act on the central nervous system, causing irreversible blockage of the postsynaptic nicotinergic acetylcholine receptors. This means that Arena and Merit should not be applied in succession, to reduce the likelihood of resistance.