Gaithersburg, MD Landscaping Rules: Tree Trimming (2026)

Gaithersburg and Montgomery County require property owners to maintain trees so they do not obstruct public sidewalks, streets, bike lanes, or sight lines at intersections. The minimum clearance standards are 8 feet above sidewalks and shared-use paths, and 14 feet above streets and travel lanes. Property owners who fail to maintain these clearances may receive a notice from Gaithersburg Public Works or Montgomery County DOT requiring trimming within a specified timeframe. If the owner does not comply, the city or county may perform the work and bill the property owner.

Montgomery County Code Chapter 49 governs trees planted within the public right-of-way along county-maintained roads, collectively known as roadside trees. Any person who wants to cut, trim, or remove a roadside tree must first obtain a permit from the county Department of Transportation, Division of Highway Services, Tree Maintenance Section. A concurrent permit from the Maryland Department of Natural Resources is also required under the state Roadside Tree Law (Natural Resources Article 5-406), which protects trees growing within the public right-of-way along state and county roads.

The dual-permit process ensures that roadside trees are only removed or significantly trimmed when necessary and that replacement planting is planned. Permit applications require a description of the proposed work, the reason for the request, and the species and size of the tree. The county tree maintenance crew may perform the work itself or authorize a licensed tree care company to proceed. Private trees growing entirely on residential property within Gaithersburg can generally be pruned or trimmed by the homeowner or a hired arborist without a government permit.

However, if the tree is a specimen tree (typically 24 inches or greater diameter at breast height, depending on species) and is located on a property subject to an active Forest Conservation Plan under Chapter 22A, significant trimming or removal may trigger mitigation requirements. Improper trimming that kills or severely damages a protected tree can result in replacement planting requirements calculated on a caliper-inch-for-caliper-inch basis, plus potential fines. Utility companies Pepco and BGE have easement rights to trim trees within their power line corridors on a regular cycle (typically every 3 to 4 years) and do not need homeowner permission, though they typically provide advance notice. Homeowners who want more aggressive trimming near power lines should contact their utility provider rather than attempting the work themselves due to electrocution risk.