I happened to look this up in reference to my own thread and might be able to help or at least offer my knowledge here.

The yellowing appears to be on older growth (as in full grown leaves not young new leaves) and they also appear to yellow near the tip first and work back to the stem which is exactly what is listed on this site as a a sign of nitrogen deficiency. Number 5 on the list if you go to the link.

Other factors can play a role here such as a very high or low pH which can determine how much of a certain element can be absorbed. Anyway, hopes this helps, personally I would get a test kit or have an analysis done on the soil to be sure. Be careful with fertilizers right now, a stressed plant can be easily burned.

Here is a link that might be useful: Plant Health

Thank you so much! Very helpful website, and helpful post! I might have done more bad than good.. i fertilized it!!

I hope i didnt burn the tree!

Best,
Sean

Cooler weather compounds issues as well.