Nitroamofoska, Urea Ukraina, Ammofos, Ammonium saltpeter, Khmelnytsia oblast.

Urea (urea) СО(НН2 )2 is the most concentrated of solid nitrogen fertilizers, contains 46% of nitrogen. It is produced in granular form with a diameter of granules of 0.2 — 2.5 mm. The granules are covered with a fatty coating. In the process of granulation, a biuret is formed. A biuret content of more than 3% inhibits plant growth, so it is best to apply urea 10-15 days before sowing so that the biuret decomposes. Urea dissolves in the soil and, under the action of the enzyme urease, turns into (НН4)2 С03. On humus-rich soils, this transformation occurs in 2-3 days, on sandy and marshy soils it is somewhat slower. Ammonium carbonate decomposes in the air, forming ammonium bicarbonate and ammonia. In order to avoid the loss of ammonia, the fertilizer should be immediately incorporated into the soil. In the soil, ammonium carbonate undergoes hydrolysis with the formation of ammonium bicarbonate and ammonium hydroxide, which alkalizes the soil solution. Then, as a result of the nitrification process, acidification occurs. When applied under rice and tea, urea acts in the same way asammonium sulfate, on light soils its action is more effectiveammonium nitrate. It is expedient to use urea as the main fertilizer, as well as for early spring fertilizing of winter and fallow crops with immediate incorporation into the soil. When using urea as a non-root fertilizer, a solution with a concentration of up to 5% does not cause leaf burn. Urea-formaldehyde fertilizers contain 37-40% nitrogen, water-soluble - 4-10%. Fertilizer does not stick, disperses well. It is promising to use them on irrigated soils and in areas with excessive moisture. They are used for tea, citrus fruits.