Jefferson County, MO Tree Protection: Parkway Planting (2026)

Section 400.4650(A) of the Jefferson County Code of Ordinances sets the street-frontage landscaping standard for new development. In the PM (Planned Manufacturing) District, one tree must be planted for every 50 feet of street frontage, whether the street is public or private, within the landscaped setback abutting that frontage. In every other zoning district, the ratio is one tree per 75 feet of street frontage. Developers may cluster or arrange the required trees within the setback if the arrangement is approved as part of the landscape plan, but clusters cannot be spaced more than 400 feet apart, and the street trees must sit within the closest 20-foot-wide strip outside the right-of-way along the frontage, unless the building setback itself is under 20 feet.

The same street-frontage standard requires one shrub for every 20 feet of frontage, also clustered or arranged within the setback as approved. In commercial and industrial districts, any parking or loading area visible from the street must additionally be separated from the right-of-way by a landscape strip at least 20 feet wide. The Director of Planning may allow deviations from the frontage standards under Section 400.4650(D) where site conditions make strict compliance unreasonably difficult.

Because this is a zoning requirement, it applies only within unincorporated Jefferson County and is reviewed as part of the landscaping and buffer plan submitted with a project's site development or subdivision improvement plans under Section 400.4570; incorporated cities such as Arnold, Festus and De Soto set their own street tree standards.