A field experiment was conducted on Beulah sandy loam to determine the influence of applications of B, N, and K on the yield, nutrient concentrations, and occurrence of growth abnormalities in cotton (Gossypium hirsutum). Symptoms indicative of B deficiency had been observed on the site the previous year. Applied B increased yield only when N was applied. Applied N increased yield only in the presence of applied B. Potassium fertilization had no effect on yield. Generally the B concentration in the plant tissue was increased by applied B, decreased by applied N, and not affected by applied K. At the early boll and medium boll stages of maturity, applied B decreased the percent total N in the leaf petioles but had no effect on that in the leaf blades. At the early square stage, applied B decreased the percent total N in the petioles when N was applied but had no effect on N concentration when no N was added. At two of three stages of maturity, applied B decreased the occurrence of ringed petioles, an abnormality considered to be a symptom of B deficiency. Applied N generally increased the occurrence of ringed petioles. At the early square stage, applied K, in the absence of applied B, increased the occurrence of ringed petioles but had no effect on the presence of rings when B was added.

The zinc (Zn) content of ten selected soils in Louisiana was partitioned into the following fractions: water-soluble, exchangeable, chelated, organic and residual. In seven of the soils, water-soluble > exchangeable < chelated < organic < residual Zn. In three of the soils, watersoluble < exchangeable < chelated < organic < residual Zn. The ten soils contained an average of 1.7, 0.9, 2.6, 4.4 and 86.4 per cent of the total in the water-soluble, exchangeable, chelated, organic and residual mineral Zn fractions respectively.

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Arsenic (As) is a widely distributed soil contaminant because of past use of As-containing pesticides. The total As content of representative soils used for agriculture in the major soil areas of Louisiana was determined. The As content of > 450 samples ranged from near zero to 73 mg/kg with a mean of 23.2

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