Cornus mas/Dogwood. Yellow spots between leaf veins.

[proninyaroslav]

This is the yamadori tree that I buy in the fall. I recently noticed yellow spots between the veins on some old leaves (first spring leaves). The tip of these leaves is also a bit dry. What could be the most likely? Underwatering, overwatering, pH problems or disease? In the spring there was a transplant with the removal of some thick roots, there were not very many thin suction roots, although thin roots grew even from the base of the trunk. The care of the dogwood was the same as for other trees (watering, fertilizing, location), and it was planted in exactly the same substrate as the rest. I water as the top layer of the substrate dries up, I apply liquid fertilizers once a week like all other trees, it stands in partial shade and only the morning sun falls on it.

 

[proninyaroslav]

This is what the affected leaves look like after a while. In the photo it looks bright green, but in reality it is much yellower.