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The compositions of percolated drainage waters resulting from the use of eight synthesized river waters of the Western USA under conditions of alfalfa (Medicago sativa L.) production in a controlled lysimeter experiment are presented. The compositions are shown to be affected by (i) the composition of the river water used for irrigation; (ii) the fraction of applied water that appeared as drainage water; (iii) the presence or absence of soil CaCO3; (iv) whether or not the drainage water is open to the atmosphere, and (v) the time of year.

Laboratory methods are presented for determining the amounts of boron that must be leached from soils to reduce their soluble boron concentrations to nontoxic levels. One method consists of an extraction of a soil sample with a 0.01M mannitol −0.01M CaCl2 solution. The second method consists of dialysis of a soil sample against a boron‐specific resin in the presence of 0.01M CaCl2 solution. Some of the soils studied were observed to “regenerate” toxic levels of soluble boron following reclamation.

No abstract

Arid‐zone soils are found to have appreciable boron‐sorption capacities in their silt and sand fractions. The site of this sorption is hypothesized to be magnesium‐hydroxy clusters and coatings that exist on the weathering surfaces of ferromagnesian minerals such as olivine, enstatite, diopside, augite, tremolite, and hornblende as well as micaceous layer‐silicate minerals.