Allen Runs A Ledger, Not A Ratio.
Every other city in this market answers one question: what do you owe for what you took out? Allen asks a different one: what’s your net position across the whole site?
Preserved trees earn tree credits per caliper inch. Removed trees take them away. What you owe is the shortfall at the end, which means preservation somewhere on the site directly pays down removal somewhere else on it. No other ordinance here works that way, and it changes what a good site plan looks like.
The practical effect is that the question stops being “which trees are in the way” and becomes “what’s the cheapest combination of keeping and removing that gets the building where it needs to go”.
The Rates, And What They Reveal.
Line the two halves of the table up against each other and the intent of the ordinance is impossible to miss.
Preserving Earns
One credit per caliper inch from six to ten inches, two per inch from 10.1 to fifteen, three per inch above fifteen. A large preserved specimen is worth a great deal more than three small ones of the same total size.
Removing Costs Double
Two negative credits per inch from six to ten, four per inch from 10.1 to fifteen. Exactly twice the preservation rate at every band, which is the clearest statement of intent in any ordinance in this market.
Above Fifteen It's Planting
From 15.1 to 24 inches, replant two inches per caliper inch removed. Above 24 inches, three per inch. At that size the ledger stops helping and the obligation becomes physical stock in the ground.
Double Is The Whole Design
Set the two rate cards side by side and the arithmetic is deliberate. Six to ten inches: preserve earns one, remove costs two. Ten to fifteen: preserve earns two, remove costs four.
Removal is priced at exactly twice preservation at every band the ledger covers. That isn’t an accident of drafting, and it’s the single most useful thing to understand before laying out a site in Allen, because it means moving a building six feet to keep a fifteen-inch tree is worth six credits, not three: three you earn and three you avoid spending.
There’s a second lever most sites never use. The city may approve credits for a healthy unprotected tree over twelve caliper inches outside the floodplain, so trees that carry no protection at all can still be worth keeping on the ledger.
The Ninety-Day Shot Clock
This provision has no equivalent anywhere else in this market, and it catches out projects that treat a permit as a permission rather than a window.
Trees to be removed must be completely off the site within 90 days of the date on the permit, extendable one time for a further 30. Miss it and the permit lapses, and a new one has to be applied for and issued before the work can continue.
On a phased development where clearing waits for financing, a tenant, or another approval, that clock runs regardless. Applying early isn’t free here, which is the opposite of the instinct on most permits.
The Three-Year Obligation Is A Signed Agreement
Several cities in this market attach a survival period to mitigation planting. Allen is the one that makes it a contract.
The owner stays responsible if a replacement tree becomes unhealthy during the three-year period following planting, and that obligation is evidenced in a tree mitigation agreement between the owner and the city. A signed instrument, not a provision somebody might mention later.
Practically, that means the aftercare is part of the deal rather than an optional extra: watering through the first two summers, and somebody actually looking at the stock in year two rather than discovering the problem in year three when the obligation comes due.
Caliper, Not Diameter.
Allen works in caliper inches throughout, where Frisco measures existing trees as diameter at four and a half feet.
They’re different measurements taken at different heights on the same trunk, and confusing them produces a number that’s wrong in your favor right up until somebody checks it. On a portfolio spanning both cities that’s a genuinely easy mistake to make, because the spreadsheet column is called “inches” in both places.
The Instrument, City By City.
What each city actually uses to regulate a tree, taken from its own code. No two of these are the same document.
Plano
Article 17 of the Zoning Ordinance. The preservation plan IS the permit, replacement runs inch for inch from 8 to 30 inches and 1.5:1 above that, and a fee in lieu is available with the Director's approval.
Frisco
Subsection 4.01 of the Zoning Ordinance. A separate Tree Removal Permit, mitigation banded as a percentage of diameter removed from 0 to 300 percent, and a survey needing two seals rather than one.
Dallas
Article X, Landscape and Tree Conservation. Protected at 8 inches, mitigation waived across the development footprint up to 70 percent of the site, and topping defined and regulated by name.
Garland
A Tree Management Plan plus Removal Authorization, class-based replacement ratios from 2:1 down to 0.25:1, and a civil penalty of $250 per diameter inch.
McKinney
Unified Development Code Article 4. Three protected tiers, mitigation doubling above 17 inches, and a perimeter zone beside existing housing where protected trees may not be altered at all.
Carrollton
Chapter 155. Replacement at 100 percent of the diameter removed, clear-cutting prohibited outright, and a survival obligation running two years past the end of the project.
Wylie
Zoning Ordinance Article 7. Enforced criminally as a misdemeanor at $100 per caliper inch, and protection is defined to exclude trees standing in easements, rights-of-way or the buildable area.
Richardson
No private-property tree ordinance at all. The tree chapter covers public trees only, which makes documentation the owner's protection rather than the city's.
- See All City Tree Ordinances