Metamitron, 4-amino-4,5-dihydro-3-methyl-6-phenyl-1,2,4-triazin-5-one, is a member of the triazinone group and is under commercial development as a selective herbicide for use in the sugar beet crop. Field tests at England's National Vegetable Research Station have given promising results also in red garden beet, a crop which occupies the ground for a shorter period than sugar beet. In order to assess possible risks to succeeding crops, determinations were made of the phytotoxic activity remaining in the soil following field applications of metamitron. The pattern of loss of activity under conditions of controlled temperature and soil moisture content was also determined.
