The split bark you see here is an extreme example of one calcium deficiency symptom in fruit and nut trees. When trees have adequate levels of calcium the bark can expand rapidly and does not split, maintaining a smooth appearance until they are decades old.
When the bark becomes so tight that it eventually splits from pressure, the flow of water and nutrients to the canopy and the fruit is also limited, which results in reduced quality and nutrient movement into the fruit.
The solution is to make sure that our soils have adequate calcium levels, and a proper balance with other cations. It is important to note that these are two different things. The threshold for disease resistant crop production is at least 1000 ppm calcium in the soil as measured by Mehlich 3 or ammonium acetate extraction. On sandy soils with low cation exchange capacity, soil reports can indicate that the calcium supply is balanced with other cations, and no more needs to be added, even when the soil only contains 400-500 ppm. In this type of scenario, more calcium definitely needs to be added to maintain crop health and performance.
