There are 4 sycamore (?) trees originally planted by the city of Pittsburgh on the street side of the sidewalk that seem to be 'dying'. All the leaves are turning brown and dropping. One of the trees is on Shady Ave, the other 3 are on Aylesboro in the 15217 zipcode. Is this a natural early drop of leaves or something wrong, and does anyone care to do something about it if there is something wrong? One of the trees is in front of my neighbor's house. The other 3 are across the street. Is there an agency or department that would adress this issue?
Sycamore trees can be subject to diseases and insect pests like lacebugs. Leaf browning can be due to anthracnose, a fungal disease. This disease can be prevalent during cool wet springs followed by a few days of warm weather. You may notice browning along the leaf veins. Anthracnose can affect oak, sycamore, ash, maples, etc. No control is necessary. Rake all fallen leaves to prevent overwintering spores.http://extension.umd.edu/learn/shade-tree-anthracnose
As you have observed, this does not kill the tree. However, it can be defoliated by mid summer. Fungicides are not practical for large trees. In general, sycamores may drop brown leaves throughout the season time. The good news is that Sycamores continue to put on new leaves as they have an indeterminate growth habit.
If you would like an onsite diagnosis regarding the health of your trees, you can contact your County or City or a certified arborist.