The tree looks like a type of maple. There may be several reasons for any decline and browning on the foliage. This does not look an insect issue. Maples roots are shallow and they can also be prone to girdling roots. The roots grow around the trunk at or below the soil line gradually strangling the trunk but we cannot say for sure. You can look for this. The tree looks like it is located in some shade due to shading from larger trees nearby and there may be root competition for moisture and nutrients from the other trees. See our publication on these types of problems http://extension.umd.edu/sites/extension.umd.edu/files/_docs/programs/hgic/HGIC_Pubs/TreesandShrubs/...
 
Also, the leaf spots looks like it may be due to a type of fungal disease possibly phyllosticta but we cannot say for sure. It is relatively common on maples, but it does not cause major harm to the trees. Rake up foliage at the end of the season. There should be enough carbodydrates stored in the root system to put out new growth next season. Here is a link on Phyllosticta https://web.extension.illinois.edu/forestry/publications/pdf/forest_health/UIUC_Leaf_Spot_Diseases_o...

There is not much to do now. All you can do is monitor for new growth next spring. You do have the option of contacting a certified arborist for an onsite diagnosis regarding the health of the tree and the best way to proceed. http://www.treesaregood.org/

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