Look up boron deficiency for apples. The recommended rate is 3 cups per acre which can be generalized to about a tablespoon per tree in the yard. Not related to your tree’s symptoms, it is also important to monitor zinc and nickel for most tree crops. Zinc is important in leaf formation and nickel is required for leafy shoot extension.
While soil analysis can tell you what is in the soil, it does very little to tell what the tree is able to extract from the soil. Leaf analysis is a better choice with most tree crops.
@Fusion_power - The second analysis I posted is a leaf analysis. The boron concentration in the leaves was in the low end of the normal range. So it doesn’t seem like the trees are having a problem taking up boron. I also had a test done on leaves that are much larger and normal looking pooled from several other trees that are healthy looking. The healthy leaves looked about the same for metals, but were closer to sufficient in sulfur.
But you are right. Zinc is deficient in both the leaves and the soil. Even in the leaves that looked normal zinc was deficient. Sulfur was less deficient in the normal-looking leaves. So it might be that there is a combined S and Zn deficiency.
The sulfur deficiency works in my favor. I may add it as elemental S and reap the benefit of soil acidification.
I didn’t know about nickel. It wasn’t an option in the leaf or soil tests.