Thank you for waiting. The symptoms you have described often point to a condition called maple decline. It is common throughout the eastern United States. It isn't one specific disease, but the results are the small leaves and dying branches you've described. Many times, there is a combination of factors that cause the decline. Lawn chemicals can be one factor. The removal of the pine trees could have had an effect if the maple's roots were disturbed in any way during the removal. Other contributing factors can be poor soil aeration, poor drainage, salt damage from salt applied to streets in the winter, high summer temperatures, drought, soil compaction, paving close to the tree, insect infestation, verticillium wilt, and root rot. Decline is often a result of several of these factors at once. Chemicals alone can kill a tree if it receives a heavy enough dose, but it is more common for there to be a combination of factors. Maple decline is often fatal.
Your best chance of saving the tree would be to consult a certified arborist. The arborist can examine your tree and the site to determine which combination of factors may be at play. You can find an arborist here:http://www.isa-arbor.com/faca/findArborist.aspx
If your budget doesn't allow an arborist, your local County Extension Agent is another option. The agent will help you figure out what is wrong, and what should be done, but will not do any of the needed treatments. This is a government program and there is no charge for their services. To find the nearest agent, go to this website, click on your state, then click on your county.http://www.csrees.usda.gov/Extension/
If you want to attempt to save the tree without help, start with an application of a good fertilizer that provides all the necessary nutrients. Scotts' Osmocote is one. It is available in garden centers and online. Make sure the tree has adequate water through any dry spells. If you see an insect infestation, use an appropriate pesticide. To be honest, most homeowners don't have success on their own. I do recommend that you call an arborist or your County Extension Agent. Even professionals will sometimes say that nothing can be done.
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