AbstractThe volatility of tri‐allate from different formulations when mixed with 2 soils containing water at 2%, 6% and field capacity was estimated in the laboratory. Volatility increased with increasing water content in each case. It was generally highest from an emulsifiable concentrate and lowest from a granule formulation with that from unformulated tri‐atlate intermediate. In a greenhouse experiment rates of loss of tri‐allate from a dry soil were similar for both emulsifiable concentrate and granule formulations, but from a wet soil and an aluminium foil dish losses were much greater from the emulsifiable concentrate. The persistence of trii‐allate from granules applied in the field was virtually the same for granules containing 2.5, 5 or 10% active ing