I was sold an Autumn Blaze Maple under the pretense that it would be one of the few trees that would grow and do well in a clay, alkaline soil. What they did not tell me is that they are extremely prone to iron chlorosis, which from what I have seen around the area, kills most of them.
Some Autumn Blaze Maples that are sick and dying
This is what mine looked like last year:
If you can get one to grow, they are beautiful trees. If yours suffer from yellowing of the leaves like mine, there may yet be hope. Keep in mind, there are lots of reasons why this might occur.
For three years I tried to help my struggling trees. Each year the leaves got smaller and smaller, and yellower and whiter. Iron chlorosis is the inability of a plant to get the iron it needs – either because there is not enough, or because it cannot absorb it. It causes the leaves to have less chlorophyl which slowly starves the tree to death. From what I have read, the Autumn Blaze has a hard time absorbing iron. Add the clay and alkaline to the mix and you get a lot of dead trees.
Here is what I tried to no avail:
- Foliar application of chelated iron. I either did not apply enough or it just didn't work.
- Soil application of the same product shown below (about 3.5% chelated iron)
What finally worked
I did two things in one final, last ditch effort to save my trees. I knew that there was only one more year in them if they did not get help.
Whitcomb's method consists of digging small holes around the tree and filling them with various nutrients. I dug a 3 inch round hole under the drip line about 12 inches deep. For each tree I dug three of these holes. I filled each hole with elemental sulfur and a micronutrient mix fertilizer (containing manganese, and other such stuff). This served to acidify the soil and provide "hotspots" where the tree can get what it needs. From the article:
The process is slow (symptoms may not improve for a year or two following treatment), but the effects can last for several years.
I dumped a lot of Miller's Ferriplus (about 6% chelated iron) all around each tree under the drip line in the spring before the leaves emerged. I re-applied shortly after the leaves emerged. I watered it in and waited for the spring rains to do the rest. I bought mine at IFA. I actually went to the store (like we used to in the 20th century). I do not think you will find it on their website.
The results have been promising so far. The limbs that had the tiny leaves sprouted tiny leaves again this year. They were yellow at first, but quickly greened. They are now tiny, but green. New growth has been spectacular – the best I have seen out of these trees. The new leaves are big and full like they should be. I will end up with over 2 feet of growth on one of them.
Here is How the Leaves Look as of July 2014