Thank you for getting back to me. I suspect your maples have more than one problem. Unfortunately, there may be nothing you can do. Those green streaks in the wood are often a sign of maple wilt. It is a fungus in the soil called verticillium. The Flame maples are particularly susceptible to this. The fungus spreads up through the roots and eventually infects the whole tree. You could try a systemic fungicide injected into the tree, but they often do little good. Trees with this disease are often simply removed.
The spots that look like insect droppings are most likely maple tar spot. It is also caused by a fungus. It actually starts out earlier in the summer with tiny yellow spots, which most of us don't notice. By late summer, the spots have become black, and more noticeable. The spots can be different sizes. Maple tar spot is considered a nuisance, rather than a threat to the tree. It doesn't do permanent damage or cause the tree to die. Usually, the best course of action is to do nothing. You can confirm this information on Purdue University's website:http://www.ppdl.purdue.edu/ppdl/expert/Tar_Spot_on_Maple.html
So you don't need to worry about the spots. The leaves stuck together and holes in the leaves are probably due to insects and other small pests, such as aphids. Some of them excrete a clear sticky substance. Some make a white web like substance. These pests have chosen your trees because they are sick. Weakened trees are often victims of pests. You could spray for insects, but if your trees have wilt, you'll be wasting your time.
Of course, it's impossible to be certain based only on an online description. I suggest that you contact your County Extension Agent to be sure of what is going on. The service is free, and the agents are very helpful. You'll probably need to take them samples from your trees so they can examine them. They'll be able to give you a certain diagnosis, and tell you what you can do, if anything. To find your agent, click on this link, then click on your county:http://solutionsforyourlife.ufl.edu/map/
If you have more questions, let me know by clicking on REPLY. I hope I am wrong, and your trees will turn out to have something more treatable than maple or verticillium wilt.