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<br />u <br />In tropical areas, this process occurs in just a few years, <br />• but in cold climates where decomposition is slow and growth can only <br />occur in a relatively short time span each year, the process can take <br />several decades to become established. <br />In mine spoil reclamation where no soil is available for <br />placement as a growth medium, essentially the same process is <br />attempted to be duplicated in an accelerated fashion. The approach <br />is to plant a diverse seed mixture into the spoil material taking <br />care to include species that in total represent a wide spectrum of <br />adaptation and tolerance curves and including a good nitrogen <br />fixing species that can survive in the soil texture. The latter <br />(finding a good nitrogen fixer) is often the most difficult <br />aspect of the whole process, and unfortunately, is also a primary <br />• key to success. The site is fertilized to provide a good nutrient <br />level for vigorous seedling growth. Subsequent fertilizations are <br />done as needed to sustain a relatively high yield. Overfertilization <br />to produce heavy growth for appearance sake is as harmful as <br />not keeping the growth at a steady pace by underfertilization. <br />The course of events, when this is done, must be closely <br />followed and at various times quick action must be taken to put <br />the development back on track. The normal sequence of events occurs <br />something like this. The first two to three years the plants <br />become established and generally have a sparse density. In the <br />fourth to seventh years, the grass in the vicinity of the <br />nitrogen fixer becomes noticeably larger and the growth is <br />. accelerated as localized nitrogen cycling begins. In five to <br />15 years, depending upon the moisture regime, the ground becomes <br />P-I-14* <br />