The maple industry is an economically important bioresource for both Canada and the Northeastern United States, with Canada being the world leader in maple products. Maple sap is collected during the natural freeze-thaw cycles which occur in the late winter and early spring. Syrup yield is directly dependent on sap yield which has links to tree health, available nutrients, forest health, environment, soil health, sap components, season length, as well as various other factors. Maple trees can tolerate a wide arrange of soils, but soils in the maple woods are often left alone due to the difficulty with addition and incorporation of the appropriate amendments. Most nutrients come from the nutrient cycling of decomposing litter and mycorrhizal associations. Nutrient deficiencies of K, P and Ca are all linked to maple decline and could be positively influenced by a fertilization program. However, improper nutrient applications could create even greater nutrient imbalances, thus leading to more dieback or decline. This review discusses current maple management practices with an emphasis on the role of soil nutrition on tree health and sap yield.
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