The main nutrient used in the growth of trees is nitrogen, and with other macro-nutrients such as phosphorus and potassium not usually deficient in our soils, fertilization activities usually focus on the addition of nitrogen as a supplement, or to otherwise improve tree growth. However, some trees may be faced with deficiencies in micro-nutrients, such as iron or magnesium, which may be corrected either directly through adding the specific nutrient, or indirectly through modifying soil characteristics such as soil acidity. We do provide free estimates for our deep root fertilization. If you want your neighbors to be jealous of your big beautiful tree in early fall when it still has its leaves and theirs does not, we recommend this! If you want your tree to be the first in the spring to have its leaves, we recommend this! This of course is the best known treatments, and for any tree disease we can not guarantee the result. We do recommend watering your trees before and after any treatments.