Q.New espalier apple tree watered daily leaves yellow.
This is one of two trees bought together but different types of apple. One is fine but the other has some yellow leaves. Next to each other on the same sunny wall.
Certified GKH Gardening Expert
This can be normal, but it can be a sign of overwatering as well. You should make sure to let the soil dry out completely down to about 2 or 3 inches or so between waterings. This will keep any infections from starting in, which can kill your tree.
This article will help you to care for apple trees: https://www.gardeningknowhow.com/edible/fruits/apples/apple-tree-planting.htm