Question
Hi Jim,
I read your Subject: Oak Tree yellow leaves, and wondered "Is it possible to
put too much iron/sulfur on a tree?"
I have about 7 (seven) Pin oaks with anemia and for the last two years I've
tried everything. First, I put just iron. Then, I tried Iron with Sulfur (But I'm
always afraid I will put to much and burn my trees.) I'm getting ready to try
what you recommended in your question/answer, the Iron, Sulfur and
Fertilizer. I only want to make sure I put enough.
These trees were all the same size when I first planted them (5 years ago.)
but they range from 10' to 20' now.
How would you recommend spacing the holes?
How many pounds per tree size?
How long should it take before I see results?
I have other Pin Oaks (about 25) that are just beautiful so I know these can be
fixed, I just don't know how? I'm willing to try any ideas you may have. Help!
Thank you,
Ali

Answer
I think I would check with the local Agriculture Extension Service and ask about getting a soil sample run. They can give you the information on how to do this. A soil sample will give you what elements are missing and how to correct them and the amount to use. It maybe as simple as adjusting the Ph so the roots can absorb the elements.
Normal fertilizer recommendation are 1 lb of 10-10-10 fertilizer per inch of trunk diameter scattered around the tree and watered in good. But since you are having more lesser element problems I would do the soil test first. Make sure that you tell the soil lab that this is for Pin oaks and they are showing signs of the leaves turning yellow.