Tree Pruning Service SOP

Purpose

Standardize residential tree pruning. The largest recurring revenue line for tree services + the work that builds long-term customer relationships (a healthy pruned tree is a 5-25 year customer).

Scope

Residential ornamental + shade trees up to 60 ft height. Excludes hazard removals (separate Removal SOP), utility-line work (call certified utility arborist), + storm response (separate scope).

Prerequisites

• ISA Certified Arborist on crew (preferred) or in supervision
• Climbing gear: saddle, ropes, lanyards, helmet w/ chinstrap, eye + ear protection
• Spurs (ONLY for removals or when no other access - not for pruning, damages cambium)
• Hand pruners (Felco 2 or equivalent)
• Hand saw (Silky Zubat 330mm)
• Pole saw + pole pruner (12-24 ft reach)
• Chainsaw 14"-18" bar (Stihl MS 201T or equivalent top-handle for in-tree)
• Aerial lift for trees > 35 ft when accessible
• Spray bottle of disinfectant (Lysol or 70% isopropyl) for tools
• Tarps + chipper

Pruning objectives (3 of 5 typical per visit)

1. Deadwood: removes safety hazard + lets tree allocate energy to live tissue
2. Crown raising: removes lower limbs for clearance over walkway, drive, building
3. Crown thinning: selective removal of small live branches to reduce density (15-20% max per visit)
4. Crown reduction: shortening limbs to reduce overall size (carefully - topping is malpractice)
5. Structural pruning: corrects co-dominant stems + competing leaders on young trees

Topping (heading cuts across major leaders) is malpractice + violates ANSI A300 - never quote it; educate the customer who asks for it.

Procedure

Step 1: Walk + plan

1. 360-degree walk around the tree
2. Identify species (pruning timing varies by species)
3. Identify defects: cavities, cracks, included bark, lean, root issues
4. Document existing damage (photo BEFORE work) - protects against claim later
5. Lockout overhead: power lines (10 ft minimum clearance for non-utility crews) + structures

Step 2: Pre-work briefing

1. Crew roles assigned (climber, ground person, drop zone watcher)
2. Drop zone clear of pedestrians + parked vehicles
3. Two-way radio or shouted commands established
4. Tools inspected (chainsaw chain sharp, ropes intact, helmet on)
5. Customer notified work is starting; access permission for adjacent yards verified

Step 3: Ascend safely

1. Tree-friendly climbing: ropes-on-natural-crotch or removable false crotch
2. NO spurs on a tree being kept (cambium damage = 5-year decline)
3. Two-rope system per ANSI Z133
4. Helmet chinstrap engaged

Step 4: Make cuts

Three-cut method for any limb > 1.5" diameter to prevent bark tear:

1. Undercut 6-12" out from final cut location, 1/3 through
2. Top cut 1-2" further out, finishing the cut so limb falls
3. Final cut at the branch collar - NOT flush, NOT a stub

Branch collar: the swollen ring at the base of the limb. Cut just outside it. A flush cut wounds the trunk + invites decay. A stub starves the wound + extends decay.

For small branches (< 1.5"): single clean cut at the branch collar with hand pruners or hand saw.

Step 5: Remove no more than 25% of live foliage per visit

ANSI A300 standard. Removing more shocks the tree + invites pest + disease. For mature trees, 15-20% is the working maximum.

Step 6: Disinfect tools between trees

Especially in disease-prone species (oaks during oak wilt season - April-July in much of U.S.). Spray + wipe pruners between cuts on diseased + healthy tissue.

Step 7: Ground cleanup

1. Chip + haul or stack to customer preference
2. Rake leaves + needles
3. Sweep walks + driveway
4. Final walk with customer + before/after photos

Acceptance criteria

• Pruning objectives met (deadwood removed, crown raised, etc.)
• No flush cuts or stub cuts
• Less than 25% live foliage removed
• No bark tears
• Drop zone restored
• Customer signed work order + has photos

Timing by species

Best pruning windows:

• Oaks (anywhere oak wilt is present): November-February ONLY (avoid April-July; sap-feeding beetles spread fungus)
• Elms: October-March (avoid Dutch elm disease vector season)
• Maples, birches, walnuts: late summer or late winter (avoid heavy spring sap flow)
• Fruit trees: late winter (dormant) for structure; summer for size control
• Evergreens (pine, spruce, fir): late winter or early spring before new growth
• Flowering trees: just after bloom (so you don't remove next year's buds)
• Dead + damaged wood: anytime - never wait for season

Common pitfalls

• Topping: malpractice. Reduces value of tree + creates hazard
• Flush cuts: trunk wound + decay
• Stub cuts: starves the wound + invites decay
• Too much at once (> 25%): shocks tree
• Wrong season (oaks during oak wilt window): kills the tree
• No two-rope: OSHA + ANSI Z133 violation
• Spurs on a keeper tree: damages cambium permanently
• No disinfectant between trees: spreads disease

Safety considerations

• Two-rope system on every climbing operation
• Aerial lift workers fall-protected + tied to boom
• Drop zone twice the limb length
• No work in storm or high wind (above 30 mph sustained)
• Chainsaw chaps mandatory on ground crew; protective wedge for in-tree
• 10 ft clearance from power lines (non-utility crews); 6 ft from secondary
• First-aid kit on truck + a designated EMT or first-aid trained ground person

References

• ANSI A300 (Part 1) Tree Pruning standard
• ANSI Z133 Safety standard for tree-care operations
• ISA Best Management Practices: Pruning
• OSHA 1910.269 (utility work proximity, non-tree-co-specific)
• Manuall internal: Tree Removal Service SOP, Tree Climbing Safety Reference