GYPSUM FOR HEAVY SOIL.

Presents a question and answer on using gypsum to break up heavy clay soil. Characteristics and uses of gypsum; Effectiveness of gypsum in reclaiming alkaline soils high in sodium found in arid parts of the West; Mechanisms by which sodium breaks down the crumb structure of soil into individual particles that pack together and prevent water and air from entering; Effects of gypsum on soil hydrogen-ion concentration; Lack of effect of gypsum for heavy soils that are salt-free.