Rich:

It looks something like nitrogen deficiency but also perhaps like wet soil. I don't think iron deficiency. How much are you watering? Apply in fertilizer? What's your soil like: clay, alkaline, drainage?

HI Fruitnut,

Thanks for the reply.

I did not do much watering, other than the sprinkler(twice a week , 10 minutes each for the grass, the tree is grown in the back yard).

My yard has typically central Texas hill country area type of soil, alkaline, with lots of rocks underneath. So when I planned the tree, I put in some soil purchased from local nursery to fill the holes, this soil is pretty sandy mixing with compost. I did a soil test, it's PH value is around 8, nitrogen based on the color of the test is kind of weak.

Water drainage is pretty good for the tree hole. I had not applied any fertilizer ever since it was grown in Feb.

Thanks
Rich