Nitrogen as a fertilizer, nutrient or pollutant Nitrogen can always be a fertilizer, nutrient or pollutant depending on the circumstances and environment in which it is found. As a fertilizer, nitrogen can be extremely useful in promoting the growth of many plants. As a nutrient, nitrogen is essential for the growth and survival of many plants. Being a pollutant, nitrogen can not only affect the plant at any given time, but can also be very harmful for many years to come. No matter where you go, nitrogen will always be a fertilizer, a nutrient or a pollutant. Nitrogen can be considered both a fertilizer and a nutrient under the right constraints. I will use citrus plants as one of my examples. For citrus growers, applying nitrogen to plants is a common and necessary practice. “Spring is the best time to apply nitrogen to citrus. Research has shown that nitrogen demand in citrus is greatest from flowering through June and the majority of supplemental nitrogen fertilizer should be applied during this time period.” . It is an important key to plant growth and development. Nitrogen is critical for citrus plants for optimal growth and yield. Without nitrogen you can see painful results for many years down the road. Citrus fruits respond readily to nitrogen nutrition. Current and past research show that if nitrogen is maintained in the leaves of citrus fruits sampled in autumn between 2.4 and 2.6% on a dry basis for oranges and between 2.2 and 2.4% for lemons, a good balance is achieved between yield, size and fruit. quality. There is evidence linking nitrogen to swelling, wrinkling, smaller fruit size and spotting, but these negative effects are most significant at nitrogen levels above 2.6%. Some growers have reduced their nitrogen application…to half the paper…damaging crops up to 8 years later. Nitrogen is an important element, whether it is found in water or some other form, but either way it can easily be a vicious pollutant. Which category do you think nitrogen should fall into: fertilizer, nutrient, or pollutant? Should you take into account how much nitrogen can help a plant with fruit size or yield? Or should we weigh heavily on how much nitrogen can harm a plant and for such a prolonged period of time? There are many ways to challenge one of these choices for or against, but none of them are perfect. Works Cited Craig Kallsen. http://cekern.ucdavis.edu/Custom Program143/Citrus Nitrogen Fertilizer.htm.Power, Sally A.; Green, Emma R.; Barker, Chris G.; Bell, J. Nigel B.; Ashmore, Mike R. 'Ecosystem recovery: moorland response to reduced nitrogen deposition.' Biology of global change 12