Hollow is not automatically dangerous, and this is where homeowners get oversold more than anywhere else on this list. A tree is a tube, and a tube carries bending load in its outer wall — a hollow stem with a thick continuous shell can be as strong as a solid one. What actually matters is the thickness of remaining sound wall relative to trunk radius, and whether the cavity is closed or has an open slot in the side. An open slot is worse than a sealed hollow of the same size because the tube can no longer resist flattening inward. Neither of those is visible by looking at the hole. In Fishers — Sunblest Farms, Avalon and Brooks Chase included, that's normally a hazardous tree removal job at $800–$5,000. Within weeks.
Why this comes up in Fishers
Duke Energy Indiana, on a five-year distribution trim cycle covering roughly 20% of line miles annually, with a minimum 14 days' notice before planned pruning and an annual vegetation report to the IURC each March 31. On top of that, Fishers issues its own annual right-of-way trimming permit to each utility under section 95.33(D), and except in emergencies, electric and communications utilities must notify the city before removing any tree.
Fishers's canopy
Fishers was not one of the 23 communities in Indiana DNR's street-tree sample inventory, so no verified species breakdown exists for the city. What is documented is that the Tree Board maintains a list of desirable and undesirable species and no species off that list may be planted as a street tree without special permission — the practical picture being a 1990s-2000s nursery palette in tight uniform age classes, with ash gone since EAB was confirmed in Indiana in 2004.
Hamilton County rules
Fishers regulates street trees, not yard trees. Under section 95.33 you need a Tree Board permit to plant, treat, spray or prune a street tree, and a separate permit to remove one, with no permit required in a genuine emergency; permits are reported to run up to 60 days with a 30-day extension on written request. Section 95.34 bars planting in any public right-of-way, required landscape easement or municipal property without a permit, and bars planting within 15 horizontal feet of an overhead utility line or five feet of an underground one. The trap is the definition: STREET TREES covers trees on real estate owned or controlled by the city AND trees within a dedicated landscape easement, which sweeps in subdivision frontage that looks like private yard. Removing a tree standing entirely in a private yard needs no permit. Section numbers, permit durations and setbacks here should be confirmed against the current Fishers code before they are relied on.
The tree lawn in Fishers
This is where Fishers diverges sharply from Indianapolis. Section 95.02 puts maintenance and removal of the tree between the street and the sidewalk or right-of-way easement line on the owner of the adjacent property, and if that owner fails to remove a dead tree or dangerous limbs after notice, the city removes them and bills the owner. But the code points both directions on cost — 95.34(D) commits the city to street tree care within the Tree Board's budget while 95.34(F) assigns owners routine care between road surface and sidewalk. Call the Department of Permitting and Inspection before assuming who pays for a removal.