Q.maple tree
The maple in the front yard has yellow leaves and looks terrible. I have tried to feed iron but must be doing something wrong. Thank you for your help.

Yellowing leaves generally indicates a watering issue, to much or to little.
Increase watering and adding 2 to 3 inches of hardwood mulch can help with moisture retention.
Inspect the plants for insects or fungus.
A soil test will help you determine what is missing or may be needed in the soil.
Here are a few links for you.
https://www.gardeningknowhow.com/ornamental/trees/maple/care-of-red-maple-trees.htm
https://www.gardeningknowhow.com/garden-how-to/soil-fertilizers/testing-soil.htm