Deficiency symptoms can be observed in the foliage. Leaves, old leaves as well as young leaves, appear uniformly a pale whitish green. Pennsylvania soils are adequately supplied with this element. Generally speaking, orchards receive enough S in rainfall. Zinc A deficiency of zinc is becoming common in Pennsylvania orchards.
Symptoms are small leaves clustered on the end of shoots.
Tissue tests are not always an accurate means of predicting a zinc deficiency. Nevertheless, since a deficiency can be very injurious and difficult to correct, zinc sprays are suggested if tissue test levels are 20 ppm or lower. Before planting an orchard or replanting an orchard where trees have shown a zinc deficiency, a soil test for zinc may be desirable. Soil test levels below 0.8 ppm zinc are considered low. Soil applications in established orchards may not be as effective as spraying the tree.