Medicine and Health Sciences Commons^™

The Isolation Of Some Nonsymbiotic Nitrogen Fixing Organisms Occurring In Some Utah Soils, Richard B. Johnson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Plants require ten elements in appreciable quantity and several others in smaller amount for their continued and normal growth. Three of these necessary elements, nitrogen, phosphorus, and potassium are most important because they occur in the soil in quantities which are usually small in proportion to that needed by the plants. Of these three, nitrogen is in most cases the limiting factor because of the ease with which it may be leached from the soil and comparatively large amount assimilated by plants. These factors coupled with the inhibiting high cost of artificially replacing it in the form of commercial fertilizers, …