SummaryThe levels of added chloride and nitrate in the topsoil of a well‐drained red clay loam have been measured throughout two dry seasons and evidence obtained that a small upward movement of dissolved salt can occur. The extent of this movement was not, however, sufficient to account for the observed accumulation of nitrate in the surface soil and it is concluded that the greater part of this nitrate was produced by some other process, such as microbial activit