News release from the City of Frederick:

The City of Frederick reminds property owners of their responsibility and the importance of trimming foliage that may encroach in the public right of way, over fences or out of yard boundaries.
With the growing season in full bloom, some plants outgrow their boundaries and can create obstacles on sidewalks. Their overgrowth creates a hazard for pedestrians, who may be forced into the street to avoid the foliage.
Growth from all hedges, bushes, shrubbery and trees must remain inside property boundaries, per City code.