What the Los Altos Tree Ordinance Means for Your Landscape Project

Los Altos lowered its protected-tree threshold from 15 inches to 12 in February 2024, and raised the removal fee from $75 to $300. If you are planning a landscape project on a mature Los Altos lot, that single change probably affects your design, your budget and your schedule before a shovel goes in the ground.

Most homeowners find out about it late. They finalize a plan, submit for permits, and then learn that the oak sitting where the new patio was drawn requires a certified arborist report, a replacement plan, a 30-day review and a 10-day public notice period nailed to a post in the front yard. That is six weeks of calendar time nobody budgeted.

It does not have to go that way. The rules are public, they are specific, and once you know them they become a design input rather than an obstacle.

What actually changed in 2024

The City of Los Altos adopted a revised tree protection ordinance on February 13, 2024, effective thirty days later. The city’s stated goal was to protect its urban forest and maintain tree canopy for carbon sequestration, while giving residents and staff clearer criteria.

Four changes matter for landscape work:

The protected threshold dropped. A tree is protected at 12 inches in diameter, down from 15. Native species are protected at 10 inches. That three-inch difference sweeps in a lot of trees that were fair game before, particularly on properties landscaped in the 1990s and 2000s where plantings have now matured past the line.

Removal fees quadrupled. The permit fee went from $75 to $300, bringing Los Altos in line with neighboring cities.

There is now a $1,200 in-lieu fee when a removed tree is not replaced on site. That money funds public tree planting.

Invasive species are free to remove. The city charges nothing for those permits, which is a deliberate incentive worth knowing about if your property carries something on the list.

Replacement is where budgets get away from people

The ordinance requires replacement in kind. If a species matures smaller than the one being removed, the city requires more of them.

The city’s own example: remove a 45-inch diameter tree, propose to replace it with a species that reaches 20 inches at maturity, and two additional trees are required. Three trees where the plan showed one.

On a typical Los Altos lot that constraint tends to reshape the design rather than the budget. Three replacement trees need three viable locations with adequate root room, and they need to make sense together visually. Discovering that requirement after the hardscape is laid out is how projects end up with trees crammed into leftover corners where they will never thrive.

We would rather find it in week one. In practice that means an arborist walks the property during design, not during permitting.

The sequencing detail almost nobody uses

Here is the part that saves real time, and it is buried in the city’s permit handout: if tree removal is part of a development application, such as a new house, an addition or a remodel, the tree work is reviewed together with that application. No separate tree removal permit is required.

Run the tree removal as its own application and you are looking at roughly 30 days of review, then a 10-day public posting on the property before removal can happen, then a 10-day window in which the decision can be appealed. Fold it into a development application that is already in process and you collapse that into a review you were waiting on anyway.

This is why we push tree decisions to the front of the design conversation on Los Altos projects. It is not caution. It is scheduling.

What the permit actually requires

The application is reviewed by the Development Services Department, and it is not a form you fill out at the counter. You need:

• An arborist report prepared by a Certified Arborist
• A replacement plan, also prepared by a Certified Arborist
• Everything else on the city’s submittal checklist

The city targets roughly 30 days for processing, though it notes this varies with workload and staffing. After the permit issues, notice must be posted on the property for at least 10 calendar days before removal. Appeals go to the City Clerk within 10 calendar days of the decision.

Dead, diseased and hazardous trees are exempt from the permit requirement. That exemption is narrower than people assume. A tree that is declining is not the same as a tree that is dead, and the judgment call belongs to an arborist, not to a homeowner who wants the shade gone.

How this changes design decisions

Three patterns come up repeatedly on mature Los Altos properties.

Hardscape gets routed around root zones. A patio or outdoor kitchen sited under a protected canopy creates a conflict between the excavation and the tree’s critical root zone. Moving the structure eight feet is cheap at the drawing stage. It is expensive once the plan is approved.

Drainage plans have to account for trees that are staying. Regrading around a protected oak changes how water sits at the trunk. Oaks in particular are unforgiving about summer water at the crown.

Lighting and irrigation get planned around permanent trees rather than through them. Trenching through a root zone can do damage that shows up two summers later, when nobody connects it back to the landscape work.

None of this is exotic. It is the ordinary consequence of designing on a lot where the mature planting is legally protected and, frankly, is most of what makes the property feel established in the first place.

A word on why the ordinance exists

It is easy to read a fee increase as bureaucratic friction. It is worth being blunt about what tree canopy actually does for property in Los Altos: it is a substantial part of why these neighborhoods look and feel the way they do. A street of mature trees is not replaceable on any timeline a homeowner cares about.

We have been building landscapes in this part of the Bay Area since 1978. The properties that hold their character are the ones where the mature planting was designed around rather than cleared. The ordinance is pushing in the same direction good design already does.

Frequently asked questions

Does a tree under 12 inches need a permit?
Not under the protected-tree provisions. Measure before assuming, because the threshold changed in 2024 and a tree that was under the old 15-inch line may be over the current one.

What if the tree is dead or dangerous?
Dead, diseased and hazardous trees are exempt from the permit requirement. Have a Certified Arborist document the condition rather than making the call yourself.

How long does the whole process take?
Budget roughly 30 days for review, plus a 10-day posting period before removal, plus a 10-day appeal window. Folding the request into an existing development application avoids running that separately.

Can I replace a large tree with a small ornamental?
Only with more of them. The replacement requirement scales with mature size, so a smaller species means additional trees.

Do these rules apply in Los Altos Hills too?
No. Los Altos Hills is a separate jurisdiction with its own regulations. Confirm which one governs your parcel before planning any tree work.

Planning a project on a mature Los Altos lot

The tree ordinance rewards early decisions and punishes late ones. Get an arborist on the property while the design is still on paper, decide what stays, and let the plan follow from there.

That is how we approach landscape work in Los Altos, and it is built into how we handle landscape design and installation generally. Every project is built by our in-house team, and the design conversation starts with what is already growing on the property.

Sources: the City of Los Altos tree removal permit process handout and the Los Altos Town Crier’s coverage of the ordinance’s adoption.