%0 Journal Article %D 1978 %R 10.48044/joa.1978.4.1.6 %J Arboriculture & Urban Forestry (AUF) %P 6-6 %V 4 %N 1 %X Baumgardt, J.P. 1977. Suitable soils: structures and characteristics. Grounds Maintenance 12(4): 80, 82-83, 85-86.The soils that gardeners work with are complex mixtures of living and nonliving materials. In these materials some substances are mineral and others are organic, which means that they once were or still are part of a living organism. Since soils suitable for gardening contain moisture in which various minerals and organic substances are dissolved, we cannot call this liquid soil water but rather soil solution. Since all soil originates with rock, the parent rock is an important consideration. Topsoil is the upper layer of soil which contains some amount of organic residues; it is aerated and well drained due to the porosity. Subsoil, on the other hand, is largely mineral in composition, it is compact and thus, scarcely aerated and drains slowly. Soil atmosphere is air that has diffused down into the soil. Soil air is rather low in oxygen as micro-organisms and root hairs use it up, but high in carbon dioxide because this gas is produced by metabolic activities of plant roots and micro-organisms.Obadal, A.J. 1977. OSHA: a businessman’s guide. Weeds, Trees and Turf 16(2): 13, 18-19.The Occupational Safety and Health Act of 1970 became effective on April 28, 1971. That date marked the end of another protracted battle between business and labor interests. Clearly, numerous legal issues arise under this Act which are of vital concern to employers. This is a short summary of what you, as employers, can do to protect yourselves from becoming entangled in the intricacies of OSHA. But be forewarned, this is not a do-it-yourself course in how to avoid OSHA problems. It is not a substitute for a sound health and safety program and appropriate legal advice. %U https://auf.isa-arbor.com/content/isa/4/1/6.full.pdf