Abstract

Baumgardt, John D. 1975. Back to basics: Soil. Grounds Maintenance 10(4): 46-47, 56, 60, 63-64, 66.

Soil is an ever-changing, delicately balanced system. The basis of soil is eroded rock —rock broken up into increasingly smaller sizes, including gravel, sand, silt, and clay. This is the inorganic portion of soil. Mixed through the inorganic particles are organic materials; some living —earthworms, nematodes, amoebae, paramecia, bacteria, fungi, and plant roots —and some dead. As mineral nutrients and air become available, the populations of living microorganisms change drastically; and because these creatures digest away organic residues, their increase or decrease is reflected in the organic level of the soil.

Plantsmen have to be concerned with soil texture and fertility; because these factors influence the health and vigor of their plants. Every gardener strives for a friable loam; that is, a soil that is easily worked, well-drained, but somewhat moisture-retentive, aerated, and fertile. Such a soil supports fine turf, thrifty trees and shrubs, and showy display plantings with a minimum of manipulations on the part of the gardener. Often soil texture and soil fertility are misunderstood, and so are the materials used to modify them. Animal manures, peats, composts, leafmold, sawdust, and the like improve soil texture, creating the proper environment for vigorous root systems. These products yield only minor amounts of nutrient elements to the soil. They are texture-improvers, and as such, are very important. Ammonium nitrate, superphosphate, and potash are chemical salts which yield, when dissolved in soil moisture, nutrients essential for healthy plant growth. The point it, you cannot garden effectively without both fertilizers and soil texture amendments.

• © 1975, International Society of Arboriculture. All rights reserved.