The chances for tree damage is so significant that the use of tree implants or injections should only be used when critically necessary. If the problem really is iron deficiency, then one treatment won't solve it.

Repeated injections add insult to injury, without addressing the real problem.....a problem with the pH of your soil.

What is the pH of your soil? How old are the trees? Is your soil reasonably well drained?

..as Rhizo said, it's a soil problem and probably pH-related at that. This can be mitigated. Most likely, your soil pH is too high, too alkaline, for that tree specie to access enough iron or manganese. Lowering the pH with soil sulfur will gradually get you where you need to be. And while the effect will then gradually be overcome by your soils natural buffering capacity, it is a simple matter to repeat the inexpensive treatment.

+oM

I agree with Rhizo and Wiscon. Probably pH. I think the red oaks need an acidic soil. I'd love to have one in my yard but they wouldn't like my clay. Nuttall oak is as close as we can come to a red oak where I am.

I wouldn't let a tree company talk me into something like that to inject into the tree. There are products you can get that will help the soil, what this guy recommended won't do that, so won't solve the problem.

Yeah, implants and other whiz-bang systems seem al high-tech and scientific. But it's all nonsense really. Injecting some needed element into the tree tissue, when the underlying condition remains in effect, is just foolishness in my opinion.

BTW, red oaks will do just fine in areas having clay-based soils. The key is that the site must also still retain the original A horizon layer, the layer where all the topsoil and humus are. It's the stripped, new subdivision situations, where this layer is absent, where the trees will really not do well. The clay itself is not the problem.

+oM

Listen to the pro, not comment guys that haven't used implants. I put iron implants in my big cherry tree 2 years ago. Leaves are dark green and healthy Before, i kept spraying with iron stuff which helped somewhat. Now I need to put an iron implant in my grape vine.

If adjusting soil pH isn’t possible or practical, I found the medicap iron to be moderately helpful on a chlorotic 25 yr old Chinese Chestnut. Helpful enough that I will repeat the application every 2 years though I still don’t have the super dark green leaves I should see on a healthy Castanea.