As we walk through the woods, we rarely see plants or trees showing nutrient deficiency symptoms. There are several reasons for this. One, the trees are generally growing in their native habitat, or a habitat to which they are adapted. Second, their root systems generally are growing unimpeded. Their extensive root systems can forage to find water and nutrients. Third, the trees are growing at their own pace, the pace that environmental conditions permit.
In nurseries, both field and container, things are usually different. Trees are not necessarily growing in their native habitat, their root systems are limited and they are not growing at their own pace. Growers are pushing the trees with irrigation and that wonderful thing called fertilizer. Growers want to maximize quality and minimize production time. Inducing all that growth however can create greater demand for nutrients. Imbalances and deficiencies can occur.
Nitrogen deficiency results in poor color and lack of growth, that ‘hungry look’. Phosphorous deficiency will often appear as weak root systems with a reddish color in the old leaves. Potassium deficiency usually exhibits itself as fairly evenly spaced necrotic spots in the older leaves, while the new leaves appear normal. You may also see leaf tip burn or burnt edges of the leaves.
With sulfur deficiency, the trees will continue to grow, but their overall color will be a lighter green than usual. Magnesium deficiency results in marginal yellowing of the older leaves, while the new leaves retain normal color. Calcium deficiency will result in stunted growth and leaves may be curled or distorted.
Lack of iron will give the classic yellowing of the newer leaves while the veins remain green. Manganese deficiency in most cases looks very much like iron deficiency. It is not easy to tell the two apart. Zinc deficiency in trees will appear as smaller than usual leaves, though the tree keeps growing. Copper deficiency in trees is pretty rare. New leaves will be severely crippled and distorted, looking almost like herbicide injury. Boron deficiency will often cause poor flowering and fruiting. In more severe cases, foliar distortion may develop.
Molybdenum deficiency is very rare in trees. It will tend to look somewhat like nitrogen deficiency, and occur in very acidic soils. Nickel deficiency is even more uncommon. In pecans it causes very tiny leaves. Harrell’s Ornamental 8-2-4 is one of the few fertilizer formulations that contains nickel.
Nutrient requirements in trees can vary significantly by both tree species and even by variety within species. The nutritional tendencies of trees are often forged by the environmental and soil conditions in their native habitat. Harrell’s has a complete line of nutritional products to correct any and all nutrient deficiencies.