T h e experimental objective was to determine effects that hydrofluoric acid, as increments derived directly from the atmosphere, induces upon soil reaction and fertility, upon seedings, upon subsequent plant growth, and upon the uptake of fluorine.Yields, fluorine uptake, and soil acidity were not affected significantly by applications of hydrofluoric acid that were in simulation to increments that would be expected to reach the soil through rain and dew in contrast to the effects induced by parallels of hydrochloric acid.In a humid region, soils of the type used would not be rendered less fertile through increments of effluent hydrofluoric acid in quantities that would be expected to come directly from the atmosphere at points not immediate to emissions. Under such conditions, and with adequacy of calcium in the soil, possible enhancements in the fluorine content of forage vegetation would be chargeable to its pollution directly from the atmosphere rather than to uptake from the soil. IVESTOCK production, floriculture, and horticulture are L purported to be affected adversely in certain localities where the atmosphere has been contaminated through fluoric emission6 from manufacturing operations. In 1943, 29 industrial pi ocessei were listed ( l a ) as causing such emissions from components iiative to the materials processed or from additive reactants, such as fluorspar, 406,000 tons of which were used in 1949 ( 2 ) .Fluoric compounds are dispelled from five distinct operatiom in the processings of rock phosphate and of slag in Maury County of middle Tennessee, but in Blount County of east Tennehsre the emissions are from a major operation in which molten cryolite is used as the solvent for alumina in the manufacture of aluminum. In both counties, however, the emissions are chiefly hydrofluoric acid, the dispersion of which may occur as a gaseom phase, as mists, as fogs, and as droplets, according to discharge volume, distance, topography, prevailing winds, and other meteorological conditions and to concomitant ocrurrence of particulates and aerosols.Many farmers in the two Tennessee counties now contend that the fluoric emissions contaminate their forage crops and that the ingestion of the contaminated vegetation is causing their liveetock to suffer the tooth, bone, and degenerative effects that spell fluorosis (1). Because of such contentions, and because the Middle Tennessee Experiment Station is located near the sevei a1 011-erations that process rock phosphate and slag in Maury County, and because the university owns an experimental farm near the aluminum operations in Blount County, the Agricultural Experiment Station inaugurated an over-all chemistry-animal husbandry study of the effects of atmospheric effluents upon plant and animal life in the two designated locales. The urgency of the situation was recognized by several organizations among those that operate in the two counties and they are cooperating and collaborating in the furtherance of the current investigation.The jointly-conducted study develop...