Beginner Gardening: Apple issues - discolored leaves, 1 by siya14

siya14 wrote:
I have 2 young apple trees approximately 2 years old. They were planted last spring and have been growing well. One dwarf mac, and one dwarf honeycrisp. Both trees in the past few weeks have discolored areas on their leaves on this years growth. They have not been fertilized this year, but mulched this and last year. Is this coloration just due to new growth or is this a deficiency? If so, what am I likely missing?

See attached images.