Answered for Danville, Hendricks County (county seat) County.
Very common here in wet springs, particularly on sycamore. One of the most over-treated problems in the trade. In Danville, the Main Street Historic District developed circa 1844–1920 across just 9 acres and 37 contributing buildings, and the Courthouse Square district circa 1865–1960 over 70 acres — those blocks hold the town's oldest and largest trees on narrow lots with sidewalks on both sides. Danville does actively manage its right-of-way canopy through a standing Tree Advisory Committee, though the specific inventory and replanting-ratio requirements attributed to Chapter 97 could not be verified. Almost never fatal on an established tree.
Danville's canopy and what's at risk
The Main Street Historic District developed circa 1844–1920 across just 9 acres and 37 contributing buildings, and the Courthouse Square district circa 1865–1960 over 70 acres — those blocks hold the town's oldest and largest trees on narrow lots with sidewalks on both sides. Danville does actively manage its right-of-way canopy through a standing Tree Advisory Committee, though the specific inventory and replanting-ratio requirements attributed to Chapter 97 could not be verified.
What to look for
Brown blotches along leaf veins, early leaf drop, sometimes twig dieback. Worst after a cool wet spring.
Whether the tree can be saved
Almost never fatal on an established tree. It looks alarming, the tree defoliates, and then it leafs back out. Most calls about it don't need a treatment at all.
Timing in Hendricks County (county seat) County
If treated at all, at bud break — but raking and binning fallen leaves does more than spraying.
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