Japanese Maple yellowing leaves

Does anyone have any idea what might be causing this yellowing of the leaves on my Japanese Maple 'Sunrise'?

How long have you had the tree planted there?

It could be many things... have you sprayed it with anything? Have you applied any fertilizer or weed n feed?

Could be sunburn, fertilizer injury, herbicide injury, nutrient deficiency, or disease.

Thanks, Dr. It was planted there in May. It was originally a part shade spot, shaded by the neighbor's huge tree. But then the tree lost some large limbs in a storm in June, and so the neighbor cut it down, and now the JM receives full sun. Also, the soil in the surrounding lawn has become wetter due to a drainspout issue which is supposed to be fixed this week.

The tree had netting over it in June while the locusts were emerging, to protect it. When I removed the netting, it had the yellowing, which seems to have spread.

I have occasionally used miracle gro liquid mixture on it that I've been using on all my plants. Also, since it began to turn yellow, I have sprayed it with fungicide, insecticide, and ironite, in case something was going on with it. :-(

My guess is that the plant was accustomed to shade and with the removal of the tree that previously provided shade the yellow and burning on the leaves could be sunburn.

Also it looks like you sprayed the tree with various products of which one or more could have caused some foliar injury? Or were they sprayed only after the symptoms were visible?

Some Japanes maples require some shade and others will acclimate to a full sun environment. I would give the tree some time and see what happens.

The yellowing and browning (picture 1) is typical of sunburn. The history of being in a bit of shade until the large tree branch broke and exposed the maple to more sun also contributes to that idea as the main problem.
The additional water from the drainage issue may have helped the tree rather than hurt when it was trying to handle the excess sun.
The last picture looks like something else, not sunburn.

Not a good idea to attack the problem first by treating then trying to find out what it is. Each -cide is somewhat toxic to the plant, and does some damage. The trick is that if the plant really has a pest problem or a fungus then the -cide does more damage to the pest or disease, and the plant can better tolerate the minor problem of the -cide than it could handle the possible damage by the pest or disease. So that makes it worthwhile to spray, when you know what the issue is.

thanks, Dr Obarr. I did not use any products until after I noticed the yellowing. The yellowing was first present after I removed the netting that was installed in early June to protect it from the anticipated locust brood.

The drainspout which is causing ground wetness in the lawn should be fixed tomorrow, and then I'll keep an eye on the tree.

Thanks, Diana. That is a good point about being more careful to diagnose the problem first. I also had not realized that the sprays were toxic to the plants, so this is good for me to know.