Hi Chris,

Thank you for your question. Would you be able to please submit a picture or describe the symptoms your tree is experiencing?

Thank you!

Hi Chris,

Thank you for the information.  Based on your soil test results and the symptoms described, it is probably due to the alkalinity of the soil. Fall is the best time to begin amending it.

Here is some information from the University of Minnesota Extension website(link included below):

"Above a pH of 7.0, iron, boron, zinc, and copper availability to the plant is limited, even if there are adequate amounts in the soil.

Just as you would add lime to acidic soil to raise the pH, you can add sulfur to basic soil to lower it. This is one of the least labor-intensive ways to reduce the pH of your soil, though it takes time. Often, annual or biannual repeat applications are necessary to actually maintain a lower pH. The basic concept is: you can add sulfur to your soil, ideally in the fall, and the microbes in your soil will break it down into sulfuric acid. This process takes time, and so by applying sulfur in the fall, you can start to reduce your pH before the next growing season.

For fruit crops, it is much easier to apply sulfur before planting than once the plants are established. Therefore we recommend reaching the correct pH range the year prior to planting and only doing additional “tweeks” later as needed.

The Nutrient Management Guide for Commercial Growers has a full list of sulfur products available to fruit and vegetable growers. Organic growers have a few options including elemental sulfur, calcium sulfate, potassium sulfate, and langbeinite.

The following rates are recommended for reducing the pH of your soil by one full unit (e.g. from 8 to 7):

In sand, loamy sand, and sandy loam soils, add 0.8 lb / 100 sq. feet, 8 lb / 1000 sq. feet, or 350 lb / acre.
In loam or silt loam soils, add 2.4 lb / 100 sq. feet, 24 lb / 1000 sq. feet, or 1045 lb / acre
Lowering the pH of clay soils is difficult due to their high buffering capacity. Because of potential salt build-up with acidifying amendments and poor internal drainage, lowering the pH of clay soils with sulfur is not recommended.
Many websites, including this UMN Extension page, mention the use of sphagnum peat to quickly lower soil pH for blueberries. While sphagnum peat can be used effectively, it is mined from a fragile ecosystem. Given the potential environmental ramifications, please consider using something else before resorting to sphagnum peat.
Do not use pine needles or coffee grounds to lower soil pH. Coffee grounds are not always acidic, and even when they are, it would take massive amounts to amend the soil. The amount of pine needles needed to meaningfully lower pH is also not realistic or feasible in an agricultural setting.
We do not yet have good recommendations about the amount of sulfur needed to bring down the pH of a high tunnel, as the right rate can depend on soil texture, moisture and calcium levels. For now, stick to the above recommendations based on your soil type.

If you're working on changing the pH of your soil, conduct annual soil tests around the same time each year to track your progress."

I have also included some helpful links with more information on how to care for your Japanese Maple.

Sources: https://extension.unh.edu/blog/2019/08/how-should-i-plant-care-japanese-maple

https://extension.umaine.edu/gardening/2021/07/12/japenese-maple-tree/

https://blog-fruit-vegetable-ipm.extension.umn.edu/2021/10/does-your-soil-have-high-ph-fall-is.html