AbstractA series of 1,2,4,5‐tetrazines has been synthesised and screened for acaricidal activity. Laboratory tests have shown several of the compounds to be highly active mite ovicides. Further examination in the field has identified a highly active compound, which gives prolonged control of mites on top fruit. The selected compound (clofentezine) is shown to be safe to mite predators and beneficial species and has been developed commercially for use on top fruit. (Clofentezine is the B.S.I. approved common name of 3,6‐bis‐(2‐chlorophenyl)‐1,2,4,5‐tetrazine).