Pruning practice guide
Topping vs. Structural Pruning: Know What You Are Buying
“Make it smaller” is not a pruning specification. Good work starts with an objective, identifies the branches involved and preserves suitable growth points.
| Practice | What it means | TCCP fit |
|---|---|---|
| Topping | Indiscriminate cuts to stubs or laterals too small to take over the terminal role. | Not aligned with the program’s preservation objectives. |
| Structural pruning | Selective cuts to improve branch architecture and reduce identified defects. | Explicitly supported when the proposal meets program rules. |
| Crown reduction | Shortening selected limbs back to suitable lateral branches to reduce height or spread. | Case by case; the objective and cut specification matter. |
| Thinning | Selective density reduction, normally focused toward the crown periphery. | Case by case; “thin the tree” alone is not a complete scope. |
| Veteran-tree pruning | Specialized pruning that may mimic natural decline to retain a late-life tree longer. | Listed by London as potentially eligible. |
Why topping is harmful
Short-term size reduction can create long-term problems
ISA guidance explains that topping can cause stress, decay, weakly attached regrowth, unacceptable risk and repeated maintenance costs. It also destroys the tree’s natural form.
London’s Tree Protection By-law includes improper pruning that fails to meet good arboricultural practices in its definition of tree injury. Whether a particular job constitutes a violation depends on the facts and City enforcement—not on a marketing label alone.
Better quote language
Ask for the objective, location and limit of work
What defect, risk or growth problem is being addressed?
Which branch, stem or crown area will be pruned?
Cleaning, reduction, structural pruning or another defined practice?
What size branches or approximate percentage of live crown will be removed?
Primary sources
Check the official rules
Program decisions are made by the City of London. These sources were reviewed on July 29, 2026.