Pollarding vs. Pruning: Key Differences Explained

When it comes to tree and shrub maintenance, two common horticultural practices often come up: pollarding and pruning. While both techniques involve cutting parts of a plant to control its growth or shape, they serve different purposes and are applied in distinct ways. Understanding the key differences between pollarding and pruning is essential for gardeners, landscapers, and tree care professionals to ensure the health, aesthetics, and safety of trees and shrubs.

In this comprehensive article, we’ll delve into what pollarding and pruning are, their historical backgrounds, purposes, methods, benefits, drawbacks, and when to choose one over the other.

What Is Pollarding?

Pollarding is a specialized form of tree management that involves cutting back the upper branches of a mature tree to a predetermined height, typically several feet above the ground, on a regular basis. This practice encourages the growth of a dense head of new shoots from the cut points.

Historical Background

Pollarding has been practiced for centuries in Europe and parts of Asia as a sustainable method for harvesting wood while keeping trees alive. Historically, it was commonly used in communal woodlands where communities relied on pollarded trees for firewood, fodder for animals, fencing materials, and timber without completely removing the trees.

How Pollarding Is Done

Timing: Pollarding is generally carried out during the dormant season (late winter or early spring) before new growth begins.
Cutting Height: The tree is cut back at a consistent height, often between 6 to 15 feet (2 to 5 meters), above ground level.
Frequency: This process is repeated every 1 to 10 years depending on species and purpose.
Tools: Large loppers, pruning saws, or chainsaws are used depending on branch size.

After pollarding, vigorous regrowth results in multiple stems or shoots emerging from the knuckles left by the previous cuts.

Common Trees Suitable for Pollarding

Some species tolerate pollarding better than others. Commonly pollarded trees include:

London plane (Platanus x acerifolia)
Lime/linden (Tilia spp.)
Oak (Quercus spp.)
Willow (Salix spp.)
Hornbeam (Carpinus betulus)
Maple (Acer spp.)

What Is Pruning?

Pruning is a broader horticultural practice that involves selectively removing certain parts of a plant such as branches, buds, or roots. The goal is to improve plant health, control growth direction, enhance flowering or fruiting, increase safety by removing hazardous limbs, or improve aesthetics.

Types of Pruning

Pruning can be subdivided into several categories:

Thinning: Removing entire branches back to their origin to increase light penetration and air circulation.
Heading Back: Cutting branches back to a bud or smaller branch to stimulate bushier growth.
Raising: Removing lower branches to lift the canopy.
Reduction: Decreasing the size of large limbs while maintaining natural shape.
Deadwooding: Removing dead or diseased branches.

When Pruning Is Done

Pruning can be done at various times depending on species and objectives:

Late winter or early spring is common for shaping and stimulating growth.
Summer pruning may slow growth or reduce size.
Deadwooding can be done anytime as needed.

Tools Used in Pruning

Pruning shears for small branches, loppers for medium branches, pruning saws or chainsaws for large limbs.

Plants Pruned

Pruning applies to almost all woody plants including trees, shrubs, fruit bushes, vines, and even some herbaceous perennials.

Key Differences Between Pollarding and Pruning

Aspect	Pollarding	Pruning
Definition	Cutting back upper branches repeatedly at a fixed height for regrowth	Selective removal of plant parts for health/shape/function
Purpose	Control size; sustainable wood harvesting; create dense foliage heads	Improve health; control shape; remove hazards; enhance flowering/fruiting
Frequency	Regular intervals (1-10 years), repeated lifelong	As needed; can be seasonal or occasional
Cut Location	At a consistent height above ground	Variable; depends on branch location & objective
Resulting Growth	Dense multiple shoots from cut points	Varies: thinning encourages open canopy; heading stimulates bushiness
Tree Impact	Can stress if done improperly but tolerates frequent cuts if started young	Generally less stressful if done correctly; improper pruning can harm plant
Suitable Species	Species tolerant to repeated cutting	Almost all woody plants
Aesthetic Outcome	Rounded dense heads	Natural shapes or controlled forms
Historical Use	Traditional sustainable resource management	Broad horticultural technique

Benefits of Pollarding

Size Control: Keeps trees smaller than their natural size, ideal for urban areas with space constraints.
Sustainable Wood Harvest: Provides continuous supply of poles/wood without killing the tree.
Longevity: Some pollarded trees can live longer because new growth replaces old weakened branches.
Safety: Removes large upper limbs that may pose hazard if left unchecked.
Aesthetic: Creates unique architectural shapes valued in certain landscape designs.

Drawbacks of Pollarding

Skill Required: Incorrect timing or cutting can lead to disease entry points or weak regrowth prone to breakage.
Initial Stress: Young trees must be pollarded early; older trees may struggle adapting.
Regular Maintenance: Needs commitment over many years; neglect leads to poor tree condition.
Risk of Decay: Repeated cuts create wounds susceptible to fungal infections if not maintained properly.

Benefits of Pruning

Health Improvement: Removes dead/diseased/damaged wood reducing risk of pests/disease spread.
Shape Control: Maintains attractive natural appearance suited for landscape design.
Growth Management: Directs energy toward productive growth, better flowers/fruits.
Safety: Removes hazardous limbs that may fall during storms.
Versatility: Applies broadly across many plants with tailored techniques.

Drawbacks of Pruning

Potential Damage: Overpruning or improper cuts can stress plants causing dieback or vulnerability.
Timing Sensitivity: Wrong season pruning may reduce flowering/fruiting or harm plant health.
Labor Intensive: Some species require careful selective pruning demanding expertise.

When to Choose Pollarding Over Pruning

Pollarding should be chosen when:

You want to maintain tree height strictly within limits due to space restrictions.
There is interest in sustainably harvesting wood without felling trees.
The tree species is known to tolerate pollarding well.
Aesthetic preference is for dense rounded heads rather than natural forms.
The site requires long-term repeat maintenance with predictable regrowth patterns.

When Pruning Is More Appropriate Than Pollarding

Pruning makes more sense when:

You desire natural tree shapes enhanced through selective branch removal.
The objective includes improving flowering/fruiting rather than size control only.
You need occasional interventions like removing deadwood or thinning dense canopies.
The plant species does not tolerate heavy repeated cutting like pollarding requires.
Safety concerns arise from isolated hazardous limbs rather than entire upper canopies.

Best Practices for Both Techniques

Whether pollarding or pruning:

Use clean sharp tools to make precise cuts minimizing tissue damage.
Cut at appropriate locations, just outside branch collars, to promote healing.
Avoid excessive removal (no more than 25% canopy at once) unless managing via pollarding cycles.
Monitor treated plants regularly for signs of stress, disease or weak regrowth.
Consult professional arborists when dealing with large mature trees or unfamiliar species.

Conclusion

Both pollarding and pruning are valuable arboricultural techniques with distinct functions and outcomes. Pollarding offers a traditional method for keeping trees compact while producing regular harvests of wood in a sustainable manner, particularly suitable for select species and urban settings requiring strict size control. In contrast, pruning serves as a versatile approach focused on maintaining overall plant health, aesthetics, productivity, and safety across a broad spectrum of woody plants.

By understanding these key differences, purpose, method, frequency, impact, gardeners and professionals can apply each technique appropriately ensuring healthy plants that meet functional requirements while enhancing landscape value.

Whether aiming for the iconic knuckled crowns of pollarded planes lining city streets or the graceful open forms sculpted by thoughtful pruning in gardens, mastering these practices enriches our relationship with trees and contributes positively to our green environments.