Surface layers of organic debris developed under established stands serve as a nutrient reservoir, releasing nutrients as the material slowly decomposes. With the exception of the most infertile soils, harvesting and site preparation increase the availability of nutrients, particularly N, to levels exceeding those required by young seedlings. On many sites this increased nutrient availability can be seen in the rapid early growth of herbaceous or woody plants that may compete with the selected pine species. This can be overcome by fertilization. Fertilization Menu Home Fertilizer Materials Fertilizer materials used in silviculture are less varied than those used in agriculture.
Dry solids predominate.
Course, dry materials that are uniform in particulate size can be evenly spread in wide swaths from ground equipment or aircraft. Deficiencies of N most frequently occur in older stands, especially on flatwoods soils and old agricultural lands. A gradual reduction in available N apparently results from its immobilization in the forest biomass. The N in fertilizers is in a form immediately available when in contact with soil moisture. Therefore, fertilizers containing P must dissolve for the nutrient to be absorbed.