Brush clearing, the removal of vegetation like shrubs and small trees, is a common land management practice with complex implications for soil erosion. While sometimes beneficial for wildfire prevention or grazing, it can also significantly increase the risk of soil loss, particularly on slopes and in areas with heavy rainfall. Examining specific case studies helps illustrate this nuanced relationship.
One compelling example comes from the chaparral ecosystems of Southern California. Studies following wildfires and subsequent brush clearing activities have shown dramatic increases in erosion rates. The removal of dense chaparral, which normally intercepts rainfall and binds the soil with its extensive root system, leaves the ground exposed and vulnerable. Heavy winter rains, common in the region, can then easily wash away topsoil, leading to mudslides and debris flows, impacting not only the immediate area but also downstream communities and water quality.
Conversely, in some managed forest ecosystems, selective brush clearing can actually reduce erosion. A case study from the Pacific Northwest examined the effects of removing dense underbrush in Douglas fir forests. The removal improved water infiltration into the soil, reducing surface runoff which is a primary driver of erosion. Furthermore, by reducing competition for resources, the remaining trees grew stronger, further stabilizing the soil with more robust root systems. This case highlights the importance of understanding the specific ecosystem and tailoring brush clearing practices accordingly.
Arid and semi-arid regions present another set of challenges. In parts of the southwestern United States, overgrazing combined with brush clearing has led to significant desertification. The removal of vegetation in these fragile environments, coupled with the compacting effect of livestock, leaves the soil highly susceptible to wind erosion. Case studies from these regions document the formation of dust bowls and the loss of fertile topsoil, impacting agricultural productivity and air quality.
These examples demonstrate the importance of context when evaluating the impact of brush clearing on soil erosion. Factors like climate, soil type, slope, and the specific type of vegetation removed all play a crucial role. Careful planning, including pre-clearing assessments and the implementation of erosion control measures such as terracing or reseeding, is essential to minimize the negative impacts and ensure the long-term health and productivity of the land. Case studies provide valuable lessons, offering real-world examples of both the benefits and the potential consequences of brush clearing, ultimately guiding more sustainable land management practices.
Brush clearing, while often necessary for land management, fire prevention, or development, can leave soil vulnerable to the erosive forces of wind and water. The exposed earth, stripped of its protective vegetative cover, becomes susceptible to topsoil loss, impacting water quality, ecosystem health, and even property values. Therefore, implementing effective mitigation strategies after brush clearing is crucial.
One of the most effective strategies is to establish a quick-growing ground cover. This could involve seeding with fast-germinating grasses or legumes, or applying a layer of mulch like straw, wood chips, or shredded bark. These measures help stabilize the soil, protecting it from the impact of raindrops and reducing surface runoff. Mulch also adds organic matter, improving soil structure and its ability to retain moisture, which further discourages erosion.
Another important strategy involves controlling water flow. This can be achieved through the construction of contour bunds or terraces, which intercept runoff and slow its velocity, preventing it from carrying away soil. Similarly, strategically placed check dams in gullies and drainage ditches can slow water flow and trap sediment, allowing the area to naturally revegetate. For steeper slopes, erosion control blankets or mats made of natural or synthetic fibers can be used to provide temporary stabilization until vegetation becomes established.
Hydroseeding, a technique where a slurry of seed, mulch, fertilizer, and a binding agent is sprayed onto the cleared area, is another valuable tool. This method provides rapid ground cover and is particularly useful on slopes and uneven terrain where traditional seeding methods might be challenging.
Finally, minimizing soil disturbance during and after brush clearing is essential. Low-impact clearing methods, such as hand-clearing or selective cutting, are preferable to heavy machinery where possible. After clearing, avoiding unnecessary foot traffic and vehicular movement on the exposed soil will help prevent compaction and further erosion.
By implementing these mitigation strategies, land managers can minimize the negative impacts of brush clearing on soil erosion, preserving soil health and protecting the surrounding environment. The chosen strategy will depend on the specific site conditions, the extent of clearing, and the available resources. However, proactive planning and implementation are key to successful erosion control and long-term land sustainability.
Brush clearing, a common land management practice, can have profound long-term effects on soil stability, directly influencing the susceptibility of an area to soil erosion. While short-term benefits like improved grazing or reduced fire risk might be apparent, the long-term implications for soil health and erosion control are more complex and often overlooked.
Initially, removing brush can seem to stabilize the soil. The dense root systems of shrubs and bushes are highly effective at binding soil particles together, and their removal can leave the topsoil exposed and vulnerable. This is especially true on slopes or in areas with high rainfall. The immediate impact can be increased surface runoff and sheet erosion, where thin layers of topsoil are washed away. This initial destabilization can persist for several years, particularly if the cleared land is not actively managed to promote soil recovery.
Over the longer term, the absence of brush cover can lead to several interconnected issues that affect soil stability. The loss of shade can lead to increased soil temperatures, accelerating the breakdown of organic matter crucial for soil structure and water retention. This reduced organic matter content weakens the soil's resistance to erosive forces. Furthermore, the lack of leaf litter and ground cover removes a protective layer that buffers the soil from the impact of raindrops, further increasing the risk of splash erosion and surface sealing.
The specific long-term effects, however, depend on factors like the type of brush cleared, the climate, the soil type, and post-clearing land management practices. For instance, clearing invasive brush species in some ecosystems can actually improve long-term soil stability by allowing native vegetation with more robust root systems to re-establish. Similarly, implementing erosion control measures like reseeding with grasses, terracing, or mulching after clearing can mitigate the negative impacts and promote soil recovery.
Ultimately, understanding the long-term consequences of brush clearing on soil stability is crucial for sustainable land management. A careful assessment of the site-specific conditions and the implementation of appropriate post-clearing practices are essential for minimizing erosion and preserving the long-term health and productivity of the soil. Simply removing brush without considering the broader ecological implications can lead to unintended consequences, including increased erosion and long-term degradation of valuable topsoil.
Brush clearing, while often necessary for wildfire mitigation, land management, and agricultural practices, can significantly impact soil erosion if not carefully planned and executed. Without the protective cover of vegetation, soil is left vulnerable to the erosive forces of wind and water. This can lead to a cascade of negative consequences, including loss of topsoil, reduced soil fertility, increased sedimentation in waterways, and degradation of water quality. Therefore, effective policy and management recommendations are crucial to minimize these impacts.
Firstly, a comprehensive assessment of the site is essential before any brush clearing activity begins. This should include an evaluation of soil type, slope, existing vegetation cover, and prevailing climatic conditions. Areas with steep slopes, highly erodible soils, or heavy rainfall are particularly susceptible to erosion and require more stringent protective measures.
Secondly, minimizing soil disturbance during the clearing process is paramount. Low-impact methods, such as selective hand-clearing or carefully controlled prescribed burns, should be prioritized over more disruptive methods like heavy machinery or whole-scale clearing. Where mechanical methods are unavoidable, techniques like designated skid trails and low-ground-pressure equipment can help mitigate soil compaction and disturbance.
Thirdly, post-clearing management is just as critical as the clearing process itself. Rapidly establishing ground cover after clearing is essential to protect exposed soil. This can be achieved through seeding with native grasses, planting cover crops, or mulching with organic materials. Erosion control structures, such as contour bunds, terraces, or check dams, can be implemented on steeper slopes to further reduce runoff and sediment transport.
Effective policy should mandate these practices and provide clear guidelines for implementation. This includes establishing buffer zones around sensitive areas like waterways, requiring erosion control plans for large-scale clearing projects, and promoting education and training programs for land managers and contractors. Regular monitoring and evaluation of cleared areas are also crucial to assess the effectiveness of erosion control measures and adapt management strategies as needed.
Finally, collaboration and information sharing are essential. Landowners, government agencies, researchers, and other stakeholders should work together to develop and implement best practices for brush clearing that balance the need for vegetation management with the imperative to protect valuable soil resources. By integrating these policy and management recommendations, we can minimize the negative impacts of brush clearing on soil erosion and ensure the long-term health and productivity of our lands.
An arborist, or (less commonly) arboriculturist, is a professional in the practice of arboriculture, which is the cultivation, management, and study of individual trees, shrubs, vines, and other perennial woody plants in dendrology and horticulture.[citation needed]
Arborists generally focus on the health and safety of individual plants and trees, rather than managing forests or harvesting wood (silviculture or forestry). An arborist's scope of work is therefore distinct from that of either a forester or a logger.[citation needed]
In order for arborists to work near power wires, either additional training is required or they need to be certified as a Qualified Line Clearance Arborist or Utility Arborist (there may be different terminology for various countries). There is a variety of minimum distances that must be kept from power wires depending on voltage, however the common distance for low voltage lines in urban settings is 10 feet (about 3 metres).[1]
Arborists who climb (as not all do) can use a variety of techniques to ascend into the tree. The least invasive, and most popular technique used is to ascend on rope. There are two common methods of climbing, Stationary Rope System (SRS) and Moving Rope System (MRS). When personal safety is an issue, or the tree is being removed, arborists may use 'spikes', (also known as 'gaffs' or 'spurs') attached to their chainsaw boots with straps to ascend and work. Spikes wound the tree, leaving small holes where each step has been.[citation needed]
An arborist's work may involve very large and complex trees, or ecological communities and their abiotic components in the context of the landscape ecosystem. These may require monitoring and treatment to ensure they are healthy, safe, and suitable to property owners or community standards. This work may include some or all of the following: planting; transplanting; pruning; structural support; preventing, or diagnosing and treating phytopathology or parasitism; preventing or interrupting grazing or predation; installing lightning protection; and removing vegetation deemed as hazardous, an invasive species, a disease vector, or a weed.[citation needed]
Arborists may also plan, consult, write reports and give legal testimony. While some aspects of this work are done on the ground or in an office, much of it is done by arborists who perform tree services and who climb the trees with ropes, harnesses and other equipment. Lifts and cranes may be used too. The work of all arborists is not the same. Some may just provide a consulting service; others may perform climbing, pruning and planting: whilst others may provide a combination of all of these services.[2]
Arborists gain qualifications to practice arboriculture in a variety of ways and some arborists are more qualified than others. Experience working safely and effectively in and around trees is essential. Arborists tend to specialize in one or more disciplines of arboriculture, such as diagnosis and treatment of pests, diseases and nutritional deficiencies in trees, climbing and pruning, cabling and lightning protection, or consultation and report writing. All these disciplines are related to one another and some arborists are very well experienced in all areas of tree work, however not all arborists have the training or experience to properly practice every discipline.[citation needed]
Arborists choose to pursue formal certification, which is available in some countries and varies somewhat by location. An arborist who holds certification in one or more disciplines may be expected to participate in rigorous continuing education requirements to ensure constant improvement of skills and techniques.[citation needed]
In Australia, arboricultural education and training are streamlined countrywide through a multi-disciplinary vocational education, training, and qualification authority called the Australian Qualifications Framework, which offers varying levels of professional qualification. Government institutions including Technical and Further Education (TAFE) offer Certificate III or a diploma in arboriculture as well as some universities.[3][4] There are also many private institutions covering similar educational framework in each state. Recognition of prior learning is also an option for practicing arborists with 10 or more years of experience with no prior formal training. It allows them to be assessed and fast track their certification.[citation needed]
In France, a qualified arborist must hold a Management of Ornamental Trees certificate, and a qualified arborist climber must hold a Pruning and Care of Trees certificate; both delivered by the French Ministry of Agriculture.[5][6]
In the UK, an arborist can gain qualifications up to and including a master's degree. College-based courses include further education qualifications, such as national certificate, national diploma, while higher education courses in arboriculture include foundation degree, bachelor's degree and master's degree.[citation needed]
In the US, a Certified Arborist (CA) is a professional who has over three years of documented and verified experience and has passed a rigorous written test from the International Society of Arboriculture. Other designations include Municipal Specialist, Utility Specialist and Board Certified Master Arborist (BCMA). The USA and Canada additionally have college-based training which, if passed, will give the certificate of Qualified Arborist. The Qualified Arborist can then be used to offset partial experience towards the Certified Arborist.
Tree Risk Assessment Qualified credential (TRAQ), designed by the International Society of Arboriculture, was launched in 2013. At that time people holding the TRACE credential were transferred over to the TRAQ credential.[citation needed]
In Canada, there are provincially governed apprenticeship programs that allow arborists' to work near power lines upon completion. These apprenticeship programs must meet the provincial reregulations (For example, in B.C. they must meet WorkSafeBC G19.30), and individuals must ensure they meet the requirements of the owner of the power system.[citation needed]
Trees in urban landscape settings are often subject to disturbances, whether human or natural, both above and below ground. They may require care to improve their chances of survival following damage from either biotic or abiotic causes. Arborists can provide appropriate solutions, such as pruning trees for health and good structure, for aesthetic reasons, and to permit people to walk under them (a technique often referred to as "crown raising"), or to keep them away from wires, fences, and buildings (a technique referred to as "crown reduction").[7] Timing and methods of treatment depend on the species of tree and the purpose of the work. To determine the best practices, a thorough knowledge of local species and environments is essential.[citation needed]
There can be a vast difference between the techniques and practices of professional arborists and those of inadequately trained tree workers. Some commonly offered "services" are considered unacceptable by modern arboricultural standards and may seriously damage, disfigure, weaken, or even kill trees. One such example is tree topping, lopping, or "hat-racking", where entire tops of trees or main stems are removed, generally by cross-cutting the main stem(s) or leaders, leaving large unsightly stubs. Trees that manage to survive such treatment are left prone to a spectrum of detrimental effects, including vigorous but weakly attached regrowth, pest susceptibility, pathogen intrusion, and internal decay.[8]
Pruning should only be done with a specific purpose in mind. Every cut is a wound, and every leaf lost is removal of photosynthetic potential. Proper pruning can be helpful in many ways, but should always be done with the minimum amount of live tissue removed.[9]
In recent years, research has proven that wound dressings such as paint, tar, or other coverings are unnecessary and may harm trees. The coverings may encourage growth of decay-causing fungi. Proper pruning, by cutting through branches at the right location, can do more to limit decay than wound dressing [10]
Chemicals can be applied to trees for insect or disease control through soil application, stem injections, or spraying. Compacted or disturbed soils can be improved in various ways.[citation needed]
Arborists can also assess trees to determine the health, structure, safety, or feasibility within a landscape and in proximity to humans. Modern arboriculture has progressed in technology and sophistication from practices of the past. Many current practices are based on knowledge gained through recent research, including that of Alex Shigo, considered one "father" of modern arboriculture.[11]
Depending on the jurisdiction, there may be a number of legal issues surrounding the practices of arborists, including boundary issues, public safety issues, "heritage" trees of community value, and "neighbour" issues such as ownership, obstruction of views, impacts of roots crossing boundaries, nuisance problems, disease or insect quarantines, and safety of nearby trees or plants that may be affected.[citation needed]
Arborists are frequently consulted to establish the factual basis of disputes involving trees, or by private property owners seeking to avoid legal liability through the duty of care.[12] Arborists may be asked to assess the value of a tree[13] in the process of an insurance claim for trees damaged or destroyed,[14] or to recover damages resulting from tree theft or vandalism.[15] In cities with tree preservation orders an arborist's evaluation of tree hazard may be required before a property owner may remove a tree, or to assure the protection of trees in development plans and during construction operations. Carrying out work on protected trees and hedges is illegal without express permission from local authorities,[16] and can result in legal action including fines.[17] Homeowners who have entered into contracts with a Homeowner's association (see also Restrictive covenants) may need an arborists' professional opinion of a hazardous condition prior to removing a tree, or may be obligated to assure the protection of the views of neighboring properties prior to planting a tree or in the course of pruning.[18] Arborists may be consulted in forensic investigations where the evidence of a crime can be determined within the growth rings of a tree, for example. Arborists may be engaged by one member of a dispute in order to identify factual information about trees useful to that member of the dispute, or they can be engaged as an expert witness providing unbiased scientific knowledge in a court case. Homeowners associations seeking to write restrictive covenants, or legislative bodies seeking to write laws involving trees, may seek the counsel of arborists in order to avoid future difficulties.[19]
Before undertaking works in the UK, arborists have a legal responsibility to survey trees for wildlife, especially bats, which are given particular legal protection. In addition, any tree in the UK can be covered by a tree preservation order and it is illegal to conduct any work on a tree, including deadwooding or pruning, before permission has been sought from the local council.[citation needed]
The protagonist in Italo Calvino's novel The Baron in the Trees lives life on the ground as a boy and spends the rest of his life swinging from tree to tree in the Italian countryside. As a young man he helps the local fruit farmers by pruning their trees.[citation needed]
Some noteworthy arborists include:
Arboriculture (/ˈɑËÂÂÂÂrbÉ™rɪˌkÊŒltʃər, É‘ËÂÂÂÂrˈbÉâ€ÂÂÂËÂÂÂÂr-/, from Latin: arboris + culture)[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[3] 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[4] 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] 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.[9][10][11][12] 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.[13] 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.[14]
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.[15] 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.
I called five different companies in the area, Rudy is the only one that not only answered but was able to come out and give an estimate and complete our project.
I had a great experience with Rudy and his crew from All In Tree Service. They came out to trim some overgrown trees on our property, and the results were amazing. They were punctual and professional, and they cleaned up all the debris afterward. I’ll definitely be calling them again!
Rudy and his team were lifesavers! We had a large pine tree dangerously close to our house, and All In Tree Service took care of it with ease. They worked quickly and safely, and the price was very reasonable. Highly recommend!
Can always count on their services! Quick to respond and provide high quality work for a fair price. Used them multiple times and will continue to give them my business for any more tree work
These guys were incredible! Israel and his crew showed up in the morning working like a well oiled machine. They removed 16 pines, ground 9 stumps and trimmed a couple hardwoods. By the end of the day two full truck loads of logs and at least three truckloads of chips were GONE! They raked and blew off everything before they left. My wife and I were amazed to watch them work. We highly recommend them and will use them again!