Pollarding is a pruning technique that dramatically shapes trees, encouraging dense growth at the top of a bare trunk. While visually striking, it's not suitable for every tree and requires careful execution. Done correctly, pollarding can extend a tree's lifespan, control its size, and even enhance its aesthetic appeal. But improper technique can lead to decay, weakness, and ultimately, the tree's demise. So, what are the best practices for successful pollarding?
First and foremost, species selection is crucial. Suitable candidates include broadleaf trees like maples, sycamores, lindens, and oaks. Avoid conifers and trees with weak branch attachments. Young, vigorous trees adapt best, ideally starting the pollarding process when the trunk diameter is between two and six inches. Older, established trees can be pollarded, but it's a more stressful process and requires gradual reduction of the crown over several years.
The initial cut is paramount. Branches should be removed cleanly, just outside the branch collar – the swollen area where the branch joins the trunk. Cutting too close damages the collar and invites decay. Conversely, leaving stubs creates weak points susceptible to breakage. The resulting "knuckles" or pollard heads will become the focal points for new growth.
Subsequent pruning, typically done annually or every other year, maintains the pollarded form and prevents the tree from becoming top-heavy. Consistency is key. Regular pruning keeps the new growth manageable and minimizes stress on the tree. Neglecting pollarded trees can lead to heavy, unwieldy branches that can split and damage the main trunk.
Timing is another important consideration. Late winter or early spring, before the sap starts flowing, is generally the best time to pollard. This minimizes stress and allows the tree to heal quickly. Avoid pruning during the active growing season, as this can weaken the tree and attract pests and diseases.
Finally, proper tool maintenance and sharp blades are essential for clean, precise cuts. Blunt tools crush the wood, creating entry points for disease. Clean tools prevent the spread of pathogens from one tree to another.
Pollarding is a specialized technique that, when performed correctly, can benefit both the tree and the landscape. By understanding the best practices and following them diligently, you can ensure the health and longevity of your pollarded trees, creating a beautiful and sustainable landscape feature.
Species Suitability for Pollarding
Pollarding, the practice of removing the upper branches of a tree to promote a dense head of foliage and branches, isn't suitable for every species. Choosing the right tree is crucial for successful pollarding and the long-term health of the tree. Some species respond vigorously to pollarding, readily producing new growth from the cut points, while others struggle, becoming susceptible to disease or decay.
Generally, deciduous trees with strong compartmentalization abilities are best suited to pollarding. Good compartmentalization means the tree can effectively seal off wounds, preventing the spread of decay. Species like London plane, lime (Tilia), and common horse chestnut tolerate pollarding well and have historically been managed this way. Oaks, particularly English oak, also respond well, although they may require a slightly different approach and less frequent pollarding. Willows, while fast-growing and seemingly resilient, are prone to decay after repeated pollarding and are therefore less suitable in the long term, although traditionally they were pollarded extensively.
Some trees, however, are completely unsuitable for pollarding. Conifers, for example, generally don't have the ability to regenerate growth from old wood in the same way deciduous trees do. Pollarding a conifer will likely result in a stunted, unhealthy tree. Similarly, trees with weak wood or those prone to specific diseases should be avoided. For example, silver maple, while a fast-growing deciduous tree, has brittle wood and is susceptible to splitting, making it a poor candidate for pollarding.
Beyond the species itself, the individual tree's health and age also play a role. Young, vigorous trees establish a good framework for future pollarding, while older, weaker trees may struggle to recover from the process. It's always best to start pollarding when the tree is relatively young, typically when the trunk reaches a manageable diameter. Attempting to pollard an old, established tree that hasn't been previously pollarded can be stressful and potentially harmful.
Ultimately, careful species selection is essential for successful pollarding. Researching the specific requirements of different species and assessing the health of individual trees before undertaking this pruning technique will ensure healthy, attractive trees for years to come. Consulting with a certified arborist is always recommended before pollarding, especially if you're unsure about the suitability of a particular tree. They can provide expert advice tailored to your specific situation and help you achieve the desired results while preserving the health and longevity of your trees.
Pollarding, that ancient practice of pruning trees to promote a dense head of foliage and branches, isn't a one-and-done affair. It's a commitment, a long-term relationship with the tree that requires ongoing management for its health and longevity. Neglecting a pollarded tree is like forgetting to feed a pet – it'll suffer and eventually decline. So, what does long-term management entail?
Firstly, consistency is key. Once you start pollarding, you need to stick with a regular schedule. The frequency depends on the species and the desired effect, but generally, pollarding is carried out every one to five years. Skipping a pollarding cycle leads to heavy, unwieldy branches that can become dangerous and eventually tear the tree apart. Think of it like a regular haircut – keeps things neat and tidy.
Secondly, proper technique is crucial. Clean cuts made just outside the branch collar minimize the risk of decay and disease. Hacking away at the branches with blunt tools creates ragged wounds that invite infection and weaken the tree. It's a bit like surgery – precision is paramount.
Thirdly, observation is vital. Regularly inspect your pollarded trees for signs of disease, pests, or structural weakness. Early detection allows for prompt treatment and prevents more serious problems down the line. A keen eye can spot the subtle signs of distress before they escalate.
Finally, adaptation is sometimes necessary. As a tree ages, its needs may change. You might need to adjust the frequency or intensity of pollarding to accommodate its growth rate and overall health. Just like us, trees go through different life stages, and their care should reflect that.
In essence, long-term pollard management is about respect for the tree. It's about understanding its needs, providing consistent care, and adapting to its changing circumstances. It's a commitment that rewards you with a healthy, beautifully shaped tree for generations to come.
Pollarding, that seemingly drastic pruning technique where you hack back a tree to its bare bones, can be a fantastic way to manage size, shape, and even encourage vibrant new growth. However, if done incorrectly, it can weaken the tree, make it susceptible to disease, or even kill it outright. Let's delve into some common pollarding mistakes and how to avoid them.
One frequent blunder is starting too late. You can't just suddenly decide to pollard a mature tree that's never been pollarded before. It's best to begin when the tree is young, ideally within its first few years, and then maintain it regularly. Pollarding an older, established tree that hasn't been trained for it can cause immense stress and lead to decay.
Another common mistake is cutting too far down. Instead of removing just the previous year's growth, some people take off way too much, cutting into the older wood. This removes the tree's energy reserves and creates large wounds that are slow to heal, inviting disease and pests. Always aim to cut just above the previous pollard points, creating those characteristic "knuckles" over time.
Using the wrong tools is another pitfall. Dull tools crush rather than cut, leading to ragged wounds that are more susceptible to infection. Sharp, clean cuts are essential. Invest in good quality pruning saws or loppers and keep them sharpened. For larger branches, a pruning saw is a must, while smaller ones can be handled with loppers.
Neglecting aftercare is also a problem. Just like any pruning, pollarding creates wounds that need attention. While painting over the cuts isn't necessary, it's crucial to inspect the tree regularly for signs of disease or pest infestation. Addressing any issues promptly will help keep your pollarded tree healthy and thriving.
Finally, inconsistency is a major culprit. Pollarding needs to be done regularly, typically every one to five years depending on the species and growth rate. Skipping years or drastically changing the pruning schedule can disrupt the tree's growth cycle and weaken its structure. Think of it like a haircut – regular trims keep things neat and tidy, while neglect leads to a messy, unruly situation.
By avoiding these common mistakes and following proper pollarding techniques, you can ensure that your trees remain healthy, vigorous, and aesthetically pleasing for years to come. Remember, pollarding is a commitment, but with the right knowledge and care, it can be a rewarding way to manage your trees and enhance your landscape.
Arboriculture (/ˈɑËÂÂÂrbÉ™rɪˌkÊŒltʃər, É‘ËÂÂÂrˈbÉâ€ÂÂËÂÂÂr-/)[1] is the cultivation, management, and study of individual trees, shrubs, vines, and other perennial woody plants. The science of arboriculture studies how these plants grow and respond to cultural practices and to their environment. The practice of arboriculture includes cultural techniques such as selection, planting, training, fertilization, pest and pathogen control, pruning, shaping, and removal.
A person who practices or studies arboriculture can be termed an arborist or an arboriculturist. A tree surgeon is more typically someone who is trained in the physical maintenance and manipulation of trees and therefore more a part of the arboriculture process rather than an arborist. Risk management, legal issues, and aesthetic considerations have come to play prominent roles in the practice of arboriculture. Businesses often need to hire arboriculturists to complete "tree hazard surveys" and generally manage the trees on-site to fulfill occupational safety and health obligations.[citation needed]
Arboriculture is primarily focused on individual woody plants and trees maintained for permanent landscape and amenity purposes, usually in gardens, parks or other populated settings, by arborists, for the enjoyment, protection, and benefit of people.[citation needed]
Arboricultural matters are also considered to be within the practice of urban forestry yet the clear and separate divisions are not distinct or discreet.[citation needed]
Tree benefits are the economic, ecological, social and aesthetic use, function purpose, or services of a tree (or group of trees), in its situational context in the landscape.
A tree defect is any feature, condition, or deformity of a tree that indicates weak structure or instability that could contribute to tree failure.
Common types of tree defects:
Codominant stems: two or more stems that grow upward from a single point of origin and compete with one another.
Included bark: bark is incorporated in the joint between two limbs, creating a weak attachment
Dead, diseased, or broken branches:
Cracks
Cavity and hollows: sunken or open areas wherein a tree has suffered injury followed by decay. Further indications include: fungal fruiting structures, insect or animal nests.
Lean: a lean of more than 40% from vertical presents a risk of tree failure
Taper: change in diameter over the length of trunks branches and roots
Epicormic branches (water sprouts in canopy or suckers from root system): often grow in response to major damage or excessive pruning
Roots:
Proper tree installation ensures the long-term viability of the tree and reduces the risk of tree failure.
Quality nursery stock must be used. There must be no visible damage or sign of disease. Ideally the tree should have good crown structure. A healthy root ball should not have circling roots and new fibrous roots should be present at the soil perimeter. Girdling or circling roots should be pruned out. Excess soil above the root flare should be removed immediately, since it presents a risk of disease ingress into the trunk.
Appropriate time of year to plant: generally fall or early spring in temperate regions of the northern hemisphere.
Planting hole: the planting hole should be 3 times the width of the root ball. The hole should be dug deep enough that when the root ball is placed on the substrate, the root flare is 3–5cm above the surrounding soil grade. If soil is left against the trunk, it may lead to bark, cambium and wood decay. Angular sides to the planting hole will encourage roots to grow radially from the trunk, rather than circling the planting hole. In urban settings, soil preparation may include the use of:
Tree wells: a zone of mulch can be installed around the tree trunk to: limit root zone competition (from turf or weeds), reduce soil compaction, improve soil structure, conserve moisture, and keep lawn equipment at a distance. No more than 5–10cm of mulch should be used to avoid suffocating the roots. Mulch must be kept approximately 20cm from the trunk to avoid burying the root flare. With city trees additional tree well preparation includes:
Tree grates/grill and frames: limit compaction on root zone and mechanical damage to roots and trunk
Root barriers: forces roots to grow down under surface asphalt/concrete/pavers to limit infrastructure damage from roots
Staking: newly planted, immature trees should be staked for one growing season to allow for the root system to establish. Staking for longer than one season should only be considered in situations where the root system has failed to establish sufficient structural support. Guy wires can be used for larger, newly planted trees. Care must be used to avoid stem girdling from the support system ties.
Irrigation: irrigation infrastructure may be installed to ensure a regular water supply throughout the lifetime of the tree. Wicking beds are an underground reservoir from which water is wicked into soil. Watering bags may be temporarily installed around tree stakes to provide water until the root system becomes established. Permeable paving allows for water infiltration in paved urban settings, such as parks and walkways.
Within the United Kingdom trees are considered as a material consideration within the town planning system and may be conserved as amenity landscape[2] features.
The role of the Arborist or Local Government Arboricultural Officer is likely to have a great effect on such matters. Identification of trees of high quality which may have extensive longevity is a key element in the preservation of trees.
Urban and rural trees may benefit from statutory protection under the Town and Country Planning[3] system. Such protection can result in the conservation and improvement of the urban forest as well as rural settlements.
Historically the profession divides into the operational and professional areas. These might be further subdivided into the private and public sectors. The profession is broadly considered as having one trade body known as the Arboricultural Association, although the Institute of Chartered Foresters offers a route for professional recognition and chartered arboriculturist status.
The qualifications associated with the industry range from vocational to Doctorate. Arboriculture is a comparatively young industry.
Tree care is the application of arboricultural methods like pruning, trimming, and felling/thinning[1] in built environments. Road verge, greenways, backyard and park woody vegetation are at the center of attention for the tree care industry. Landscape architecture and urban forestry[2][3] also set high demands on professional tree care. High safety standards against the dangers of tree care have helped the industry evolve. Especially felling in space-limited environments poses significant risks: the vicinity of power or telephone lines, insufficient protective gear (against falling dead wood, chainsaw wounds, etc.) and narrow felling zones with endangered nearby buildings, parking cars, etc.. The required equipment and experience usually transcends private means and is often considered too costly as a permanent part of the public infrastructure. In singular cases, traditional tools like handsaws may suffice, but large-scale tree care usually calls for heavy machinery like cranes, bucket trucks, harvesters, and woodchippers.
Road side trees are especially prone to abiotic stress by exhaust fumes, toxic road debris, soil compaction, and drought which makes them susceptible to fungal infections and various plant pests[4] like the spotted lantern fly.[5] When tree removal is not an option, because of road ecology considerations, the main challenge is to achieve road safety (visibility of road signs, blockage-free lanes, etc.) while maintaining tree health.
While the perceived risk of death by falling trees (a part of the "tree risk" complex) is influenced by media and often hyped (the objective risk has been reported to be close to 1 : 10.000.000, almost as low as death by lightning),[6] singular events have encouraged a "proactive" stance so that even lightly damaged trees are likely to be removed in urban and public traffic surroundings.[3] As a tree ages and nears the end of its safe useful life expectancy (SULE),[7] its perceived amenity value is decreased greatly. A risk assessment normally carried out by local council's arborist to determine the best course of action.[8][9] As with all public green spaces, trees in green urban spaces and their careful conservation is sometimes in conflict with aggressive urban development even though it is often understood how urban trees contribute to liveability of suburbs and cities both objectively (reduction of urban heat island effect, etc.) and subjectively.[10][11][12][13] Tree planting programs implemented by a growing number of cities, local councils and organizations is mitigating the losses and in most cases increasing the number of trees in suburbia.[14] Programs include the planting of 2 trees for every 1 tree removed, while some councils are paying land owners to keep trees instead of removing them for farming or construction.[15]
The voluntary industry consensus standards developed by TCIA, resulted in the ANSI A300 standard, the generally accepted industry standard for tree care practices including trees, shrubs, and other woody plants.[16] It includes the following parts:
Urban Forestry maintains 4.1 million trees on public property, which includes an estimated 3.5 million trees within Toronto's parks and ravines, and approximately 600,000 trees on City streets. ... The focus of our maintenance service is shifting progressively from reactive maintenance to proactive maintenance.
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Ho Chi Minh City has announced a plan to move and cut down 300 trees on Ton Duc Thang Street in District 1 to make space for a bridge connecting to District 2 and a metro station.