In the past decade, the lawn care sector of the turfgrass industry has been expanding at a tremendous rate. A healthy, green lawn not only provides aesthetic pleasures for the homeowner, but can increase property values as well. Fertility programs used in the industry include a number of nitrogen (N) sources that can be applied in dry and/or liquid forms. Because of its versatility, liquid fertilization is rapidly becoming the most popular method of applying fertilizers to turfgrass. It has been estimated that at least 60 per cent of the industry is applying liquid fertilizers (Early, 1981). Fluid fertilizer consumption in general has been increasing in the United States, and presently accounts for JO per cent of all fertilizer tonnage applied annually. The lawn care industry has significantly contributed to this increase (Early, 1981).