If new growth comes in yellow or yellow-patterned in spring, there are some typical culprits:
Nitrogen deficiency - uniformly yellow or pale green leaves, remedied by nitrogen application
Iron deficiency - yellow leaves with distinct green veins, remedied by supplemental chelated iron and improving soil aeration
Zinc deficiency - small yellow leaves with distinct green veins, often that form in tufts or rosettes, remedied with chelated zinc and improving soil aeration
Manganese deficiency - wide yellow patches between green veins, remedied by manganese chelate and improving soil aeration
Overwatering: Consistently yellow leaves may be an indication that the tree is overwatered. In early spring, this may be from rain. If it’s been a while since it’s rained, check for soggy soil. If you find some, re-evaluate the irrigation method and frequency. If that doesn’t correct the issue, you may need to re-evaluate the tree’s place in the yard.