Ignoring an extremely low soil pH can lead to severe yield reduction if lime is not applied, as illustrated in Table 1. Nutrient availability and herbicide activity are influenced by soil pH. The availability of most nutrients is greatest at near neutral pH levels. The effectiveness of some herbicides is markedly affected by soil pH, and pH must be considered in herbicide selections and their rate of application. The following discussion addresses acid soils and liming. Causes of Acid Soils Acid soil conditions arise from several factors.
Some soils are naturally acidic because of the parent material from which they form.
Most acid soils exist, however, because of soil develop-ment and management. Climatic conditions during soil profile development affect water movement through soil. In areas with higher rainfall, greater leaching of basic cations results in lower soil pH, a relatively slow acidification process.