Why Attorneys Hire an Arborist Expert Witness

Posted on February 3, 2022 by landscapeexpert

Whether an attorney represents a plaintiff or defendant, they hire an expert who will provide compelling testimony to support their client. Sometimes, multiple experts from a variety of disciplines may be required. When should an attorney consider hiring a certified or registered consulting arborist as an expert witness?

Trip, slip and fall accidents caused by tree roots damaging concrete sidewalks, asphalt streets, patios, and decks.
Tree failures, forensic tree risk assessment to determine open and obvious?
Appraisal(s) to establish the pre-casualty tree value prior loss due to fire, vandalism and trespass.
Determine whether an owner, individual or company satisfied the arboriculture industry standard of care.

Living with trees implies accepting a certain amount of risk in exchange for the wonderful benefits trees provide. While the risk of a tree limb or whole tree failure resulting in a fatal injury is low, hazards caused by trees that result in personal injury or property damage lawsuits are not uncommon.

Tree species and proximity to infrastructure may be a factor in accidents with personal injury or property damage. Tree roots seek out moisture regardless of their location. Structural roots emanate from the trunk to the edge of the crown, also known as the drip line, then small moisture absorbing root grow far beyond. Tree root systems may grow 1.5 times the tree crown diameter.

Trip, Slip and Fall Accidents

In the urban environment, tree proximity to hardscape may result in roots growing beneath concrete sidewalks and paved streets while seeking moisture. Roots will grow into adjacent water meters and sewer laterals, especially older leaking, permeable infrastructure. Once established beneath a paved surface, a root continues growing, over time enlarging in diameter.

Over time, these surfaces may begin to lift along the crack or expansion joint. Adjacent sidewalk panels may lift several inches, resulting in a hazardous condition for pedestrians and bicyclists.

Uplifted sidewalk panels resulted in bicyclist personal injury lawsuit

After sidewalk was removed, large structural roots were observed beneath the sidewalk.

Multiple roots damaged the sidewalk, created the hazardous condition and resultant accident.

Eventually root enlargement lifts concrete infrastructure, including water meter boxes and sidewalks. Cracks may develop across a sidewalk panel, in my experience, most concrete sidewalk uplifts occur along an expansion joint.

In their pursuit of moisture, roots from neighboring trees ignore property lines. They can grow beneath garage slabs and foundations, especially in situations where there has been a water or sewer leak beneath the slab. Moisture discharged beneath slabs, footing and foundations create an attractive environment for root development.

Neighbor’s Ficus tree root grew beneath their garage slab, resulting in property damage lawsuit.

Roots suspected of lifting sidewalk panels and water meter box that resulted in personal injury lawsuit.

After sidewalk was removed, large roots observed growing around the water leaking water meter.

Installing street trees within small concrete confined planters is an invitation for root damaging infra-structure. Leaking water meters, fittings and sewer connections increase soil moisture, an invitation for root growth.

A root penetrating a leaking sewer lateral or potable water meter pipe or fitting will quickly establish a mass of roots within and surrounding the pipe. Root growth may continue from the sewer lateral into the public sewer main. Over time, the root growth may block or cause a sewer back up to neighboring properties.

Roots deform a sewer lateral beneath garage slab.

Section of removed sewer lateral filled with roots.

Improperly designed, installed or maintained sprinkler systems may result in over-spraying paved pedestrian sidewalks. Regardless of cause, their is no reason to allow sprinklers to over-spray onto paved surfaces, it wastes a vital resource while creating an obvious slip and fall hazard.

Park sprinklers over-spraying a public sidewalk, resulted in a personal injury lawsuit.

Tree failures and forensic tree risk assessment

Tree limb and whole tree failures may result in personal injury and property damage lawsuits. Whole tree failures may occur due to loss of load bearing structural roots, whether due to root rot disease, construction impacts, mechanical root damage, or soil failure. Limb drops may occur for a variety of known reasons, typically the failure occurs during a weather event. Sometimes, a tree will drop a limb for unknown reasons, referred to as sudden or summer limb drop. Stems may contain defects such as cankers, decay, and cracks that may be predisposed to failure when enough force exceeds the wood carrying capacity. Forensic tree risk assessment may determine why the tree failed and whether the defects were open and obvious.

Stem failure resulted in personal injury and property damage lawsuit.

Tree and landscape appraisal for fire damage, trespass and vandalism

California has suffered countless wildfires the past two decades, resulting in substantial property damage. Tree appraisal for loss due to fire may be an important aspect in legal cases, especially when several major utilities are under scrutiny for causing wildfires.

The same holds true for tree loss or diminution in value due to trespass and vandalism. You may love your tree, but your neighbor may not. Neighbors frequently engage in tree disputes, sometimes resulting in trespass and vandalized trees. You may love your tree, but your neighbor may not.

Avocado groove scorched from wildfire in Fallbrook. Appraisal performed for insurance and tax purposes.

Oak tree property damage claim due to Thomas fire.

Tree and landscape appraisal for property damage lawsuit caused by Thomas fire mudslide.

Palm tree nursery burned due to vandalism, appraised palm value for property damage lawsuit.

Bamboo hedge poisoned by neighbor, property damage lawsuit.

Tree loss due to neighbors pruning, resulting in property loss lawsuit.

Arboriculture standard of care

Tree service contractors may become involved in a lawsuit for failing to satisfy the industry standard of care. When a tree failure occurs, the landscape maintenance or tree care contractor may find themselves as defendants in a lawsuit. A plaintiff may contend the landscaper or tree care company should have known the tree had defects but was the contractor responsible for risk assessment?

A C-27 landscape contractor may not be a certified arborist or provide arboricultural tree care, certified arborist may not be a trained or knowledgeable of Tree Risk Assessor Qualified, (TRAQ).

To determine a contractor’s standard of care, I examine their membership in industry associations such as the California Landscape Contractor Association, (CLCA), the International Society of Arboriculture, (ISA), the American Society of Consulting Arborists, (ASCA), and Professional Tree Care Association. I determine whether the certified arborist and tree care professionals adhere to the American National Standards Institute, (ANSI) A300 arboriculture standard practices and Z133 safety requirements. I check their standing on the California State Licensing Board.

In summary, personal experience, education and training are essential qualifications an attorney looks when selecting an arborist expert witness. Having expertise in multiple disciplines is an added benefit. My qualifications as a professional horticulturist, a C-27 landscape contractor, a certified arborist, registered consulting arborist and tree risk assessor qualified and land development manager enable me to opine on a broad array of landscape, tree, plant and land development issues.

Tree Roots Lifting up Sidewalk?

Posted on August 11, 2020 by landscapeexpert

Who is Better Qualified to Opine on Root Damage, Civil Engineer or Certified Arborist?

I was retained by a defendant attorney to determine whether her client’s tree was responsible for lifting the adjacent civil sidewalk that resulted in a plaintiff trip and fall lawsuit. Based on the photographs and tree species, White mulberry (Morus alba), I was fairly certain her client’s tree was responsible for the sidewalk damage.

The attorney retained me and requested a site inspection and tree root assessment. I trenched adjacent to the sidewalk and within a short time, encountered a three-inch diameter root growing under the sidewalk. Further excavation revealed a network of two to four-inch diameter roots that had grown under the sidewalk, resulting in the tree roots lifting up the sidewalk panel, creating a hazardous condition resulting in a trip and fall accident.

I informed the attorney that tree roots lifting up the sidewalk, or root encroachment from her client’s tree resulted in the sidewalk damage, she said her civil engineer expert claimed it impossible for a tree root to lift a concrete sidewalk. I questioned the engineers knowledge and experience with trees, was the civil engineer a certified arborist or horticulturist?

Although the answer was no, she felt his qualification as a civil engineer was superior to my qualifications as a certified arborist, tree risk assessor qualified, registered consulting arborist and a college educated horticulturist. Her dilemma was having two experts who disagreed and she requested I alter my opinion.

I told the attorney altering my opinion to suit her needs was unethical, and I removed myself from the case.

What Causes Tree Roots To Lift up a Sidewalk?

The common myth is trees have tap roots that grow straight down into the soil. While this may occur in very deep, loam soils, the reality is most containerized nursery grown trees lose their tap root in the container. Once planted in our poor Southern California soils, when the tap root encounters physical soil obstructions, such as rock, clay or hardpan, the tap root divides and grows multiple roots around the obstacle, forming a fibrous root system. Tap root grows into fibrous root system.

Trees require a spreading root system to maintain structural stability. Trees dissipate energy generated during a storm or wind event by transmitting leaf, limb and trunk movement down to the roots. A spreading root system anchors the tree movement and dissipates the energy far more effectively than a single tap root system.

Most tree roots grow within the top 24-inches of the soil horizon. Roots in top 24″ of soil. Over time, structural tree roots (2-inch diameter and greater) growing within a shallow soil adjacent to sidewalks, footings, foundations, walls or othersub-surface infrastructure may cause damage.

Just as a twig grows into a branch, and then a limb, roots increase in length and circumference. Irrigation water, sewer or water service leaks increase subsoil moisture beneath sidewalks or garage slabs, creating a perfect environment for root growth.

Cracked garage slab

As the root circumference increased, it exerts pressure on the concrete slab or footing above the root. Depending on the species, root diameter might increase 1/8-1/4” annually.

Within five to eight years, a small feeder root may grow to one-inch in diameter or greater.

Ficus root cracked the garage slab

The root growth may be compared to the action of a hydraulic jack, as the circumference increases, the upward pressure on the sidewalk or slab may crack and or eventually cause tree roots to lift the sidewalk. Concrete lifting may often occur at an expansion joint between concrete panels

Sidewalk lifted at expansion joint

Root network beneath sidewalk.

Roots seek out soil moisture, they can and will grow under walls, footings and garage slabs. Roots are opportunistic, leaky plumbing, old cast iron sewer lateral or water services contribute to the soil moisture needed for roots to flourish.

Sewer lateral root damage

Roots may infiltrate pvc, abs and cast-iron pipe through even the smallest of cracks or holes.

Once inside, the roots expand in size and quantity, eventually completely clogging the utility.

If the tree crown has grown over a sidewalk or adjacent structure, it is a reasonable assumption structural roots (two-inch diameter and greater) have grown under the sidewalk, slab or footing.

Root growing under house footing

Planter areas confined by concrete pose one of the greatest risks for root damage. City sidewalks often incorporate small, square planters within the sidewalk easement.

Roots lifting water meter and sidewalks

Confined planters quickly fill with structural roots, as well as damaging girdling root. As the tree crown grows, so to do water absorbing feeder roots. Over time, root mass and size increases, structural roots may begin to grow beneath concrete improvement while seeking out moisture.

Leaking water meter, high soil moisture, confined growing space.

The tree pictured above and to the right had a leaky water meter adjacent to the small sidewalk planter. The leaky service provided idea soil moisture conditions for the roots to lift the water meter box, adjacent sidewalks and crack the curb and gutter.

Preventative measures to minimize root encroachment include a variety of root barrier methods. All root barrier systems work best when the tree is installed. Once roots have enlarged and matured, barrier mitigation is not successful.

In summary, our Southern California poor, shallow soils do not support deep tree tap root systems. Most trees grow fibrous spreading root systems. Structural roots emanating from the root collar extend to the edge of the tree crown, (drip line). Most structural roots growing beneath sidewalks range from two to four inches in diameter, lifting sidewalk panels on average one-two inches. Trees growing in confined planters or adjacent to concrete, utilities or foundations may develop structural roots capable of lifting, cracking or damaging adjacent improvements.

Dealing with legal issues due to tree roots lifting up a sidewalk?

Attorneys should select an expert based on the case criteria, not simply a title, license or certificate. Choose an expert most appropriate to address the cause of the problem and develop opinions based on sound, industry practices.

Arborist Online Learning Opportunities in the Covid Era

Posted on May 12, 2020 by landscapeexpert

In a recent blog, I discussed using online media for a site online site inspection involving a Torrey pine tree root conflict with adjacent asphalt paving. That marked the first time I used an online media tool rather than being physically present at the site. My client and I used Facetime to conduct the real time inspection.

As the restrictions ease, I believe the use of online media such as Zoom, Hangouts, Facetime etc will increase. I have already presented this concept to a legal client in Northern California concerning an irrigation inspection. Do I really need to fly from San Diego to San Francisco, rent a car, drive to the site, observe irrigation defects, then reverse the process returning home or, can I watch the inspection over the web? The level of scrutiny required depends on the individual case.

A slide from Dr. Smiley’s presentation

Like so many other industries, the tree industry is rapidly adapting to the new Covid – 19 reality. Today, I attended an online Zoom seminar titled Sidewalks, Urban Plazas and Tree Roots. This seminar was presented through the ISA Southern Extension. I believe it was originally going to be part of a “normal” ISA Southern Association Annual meeting that was cancelled due to Covid.

The online presentation occurred through Zoom with over 1000 arborists throughout the U.S. and other countries attending. The topic concerned tree roots damaging sidewalks, presented by Dr. Thomas Smiley. Once a few technical glitches were adjusted, the presentation was almost identical to what I had experienced attending many seminars.

The slides presented alongside the audio streaming from Dr. Smiley was easy to view. I became immersed in the content and found myself taking pics of some of the slides. The topic provided test data results using different techniques designed to reduce root intrusion beneath sidewalks.

Incorporating root growth inhibitor practices

The presentation lasted an hour, same amount of time I’m accustomed to when attending a seminar. Although I already knew a great deal about the topic, I still came away with new information for use in my practice, including a great specification detail incorporating multiple root growth inhibitor practices that may reduce sidewalk damage due to roots.

In the past month, I’ve been able to continue my consulting practice from my home office. I’ll continue to utilize more online media tools, whether for learning, conducting site inspection work, and client meetings. I believe these new opportunities are one of the (few) beneficial results from the Covid-19 virus.

I recently provided a client with a proposal to develop landscape maintenance specifications for commercial properties located in several different climatic regions. The proposal did not include any site visits. All data collection would occur online through various means. Using online data collection versus conducting multiple site visits saved the client thousands of dollars.

I’m looking forward to these new opportunities utilizing online media sources as potential replacement for physical presence. Hopefully it will prove an efficient, effective, cost saving technique without sacrificing product accuracy.

Online Site Inspections with Corona Virus: A New Paradigm?

Posted on April 24, 2020 by landscapeexpert

The corona virus and resulting stay at home order has prevented me from scheduling or attending site inspections. I require site inspection for most forms of consulting work, including as a consulting arborist or expert witness.

Tree failures, health and risk assessment
Tree inventories
Tree and nursery appraisals
Tree roots and infrastructure damage.
Landscape appurtenances creating trip and fall hazard.
Obscured landscape hazards, grade changes
Irrigation operation, maintenance issues

A client wanted me to attend and observe asphalt paving taking place adjacent to an 80 year old Torrey Pine. I had previously consulted on preserving this tree during construction on an adjacent property. The client was repaving his driveway on the alley, the pine is right on the edge of the paving.

Due to California stay at home orders, I informed the client I could not be present to observe the paving to make recommendations, so we used the Facetime app and did an online site observation whereby I watched in real time as the work was being performed. I was able to give the client recommendations in real time.

Moistened towel protect surface roots

He was concerned about root damage, and rightly so. Some of large buttress roots would be impacted by the paving. Instead of cutting, I recommended covering the roots with wet towels, fabric etc, then placing moistened sand base, then pave over the roots.

Moistened sand placed over protected roots

As terrible as it is, the corona virus has created many new ways for industries to re-invent how they do their business. This was the first time I have attempted on online site inspection and it worked! This may not be applicable for the types of investigations I perform, but there is a great new tool I can use for certain types of investigations during stay at home and even beyond.

Asphalt paving over protected roots

The financial savings for the client are obvious. Travel costs for me to travel to Los Angeles, Orange or Inland Empire typically range from $500 to $1000 or more if hotel stay is required.

Not all inspections can be performed remotely. Forensic investigations that require measurements, excavations, sampling, testing etc may not be applicable.

Since this is new to me, it will take some real time client cases for me to determine how and when I can utilize this new tool.

Old Growth Redwood Destruction Continues

Posted on April 21, 2020 by landscapeexpert

I read an L.A. Times article discussing ongoing logging of redwoods in Humboldt County. In a battle spanning several generations, tree sitters and eco-activists are putting their bodies on limbs in redwood tree tops to prevent logging.

This is not the first time tree activists have climbed hundreds of feet up old growth redwoods to prevent logging the tree and surrounding trees. It reminded me of a remarkable novel I read called “The Overstory” by Richard Powers. The novel is about people and their interaction with and the affect specific trees and forests.

It primarily focuses on loss of old growth redwoods and firs in the pacific northwest and activists actions to prevent tree and habitat loss. However, the novel was historical, taking place several decades ago. Yet it appears old growth logging in Humboldt county continues to in present.

I recently visited, camped and explored the Jedediah Smith State and National Redwood park, not far from where present day logging takes place. For me, the thought of logging off trees that are hundreds to over a thousand year old is difficult to accept.

We have commercial redwood farms for harvesting lumber. Of course, it does not possess the grain, size, color and characteristics of true old growth redwood trees. If we want future generations to be able to view and experience the incredible creation of a true, old growth tree, we MUST stop logging and preserve this resource.

Joshua Tree Extinction by End of Century?

Posted on April 14, 2020 by landscapeexpert

I just read an article in the Los Angeles Times about a potential listing of the Joshua tree as an endangered species. The western Joshua tree, Yucca brevifolia, is one of two genetically distinct species that occur in California. It range extends from Joshua Tree national park westward along the northern slope of the San Bernardino and San Gabriel mountains, northward along the eastern flank of the Sierra Nevada and eastward to Death Valley.

Approximately 40% of the western tree range is on private land, the eastern range is centered in the Mojave National Preserve and eastward into Nevada.

After decades of climate change, development, drought and wildfires, the species is facing a rapidly increased the risk of extinction. State Department of Fish and Wildlife Commission will decide in June whether to accept the department’s recommendation to declare the tree an endangered.

As usual, there are two sides to the issue. Conservationists see this as a triumph of state environmental law while critics claim it as a misguided overreach because Joshua trees are already protected under many city and county ordinances and within the 800,000 acre national park.

Environmentalists argue existing state and local ordinances are largely inadequate at protecting species habitat loss, the endangered species listing will finally provide a statewide protection for the species, including requiring wildlife managers devise a recovery plant for the species, which could limit development in SoCal real estate.

The Joshua tree exists in high desert communities such as Yucca Valley or Hesperia, communities with lower average median household incomes. They are concerned the listing would impose additional burdens to real estate development, making it tougher to improve their property or curtail new development in their communities.

However, researchers warn time is running out. The tree’s range is contracting at lower elevations, its reproduction has come to a halt. Trees are failing to reproduce at lower, hotter elevations. They could become extinct in California by the end of the century!

This would be a terrible outcome for a truly incredible species. This remarkable species deserves protection. I believe this tree, in its own way is as majestic in its high desert setting as the coast redwood. These are species distinct to our California heritage. The Joshua tree deserves protection for our future generations to enjoy, marvel and be uplifted by this unique species.

Download a pdf of the article here: Los Angeles Times – eNewspaper

California Olive Trees Dying from Exotic Pest Infestation

Posted on April 10, 2020 by landscapeexpert

Olive tree displaying decline symptoms

With so many trees dying in natural and landscape settings, I’ve observed a disturbing trend throughout San Diego, and I assume most of the state. Property owners allowing dead and declining trees, palms and shrubs to remain in place. The problem with this practice, aside from aesthetics, is the dead plant may serve as a vector, whereby flying insects such as beetles, leaf hoppers, spittle bugs etc. may spread the disease to other uninfected trees.

Over the past decade, drought and climate change has taken a toll on millions of trees throughout California. Drought weakened trees succumb to secondary invaders such as wood boring bark beetles. There appears to be a continuous proliferation of new exotic pests resulting in diseases that are killing millions of trees in nature and within our urban forests and residential landscape settings.

Gold spotted oak borer

First collected and identified in 2004 was the gold spotted oak borer, (GSOB). This flathead borer is responsible for killing over 100,000 live and black oaks in San Diego County alone. There is no effective prevention or cure.

Reports of the disease known as citrus greening, previously confined to China, appeared in Florida, threatening the entire U.S. industry. The disease is a vector-transmitted pathogen by the

Citrus damaged by Asian citrus psyllid

Asian citrus psyllid. This disease ravaged Florida citrus growers. Once infected, there is no cure.

Another exotic pest first detected in Southern California in 2003 has been infesting hundreds of different species and is now established throughout the southland.

The Polyphagous shot hole borer is a small ambrosia beetle responsible for transmitting Fusarium disease to many tree species including avocado,

Sycamore bleeding from shot hole borer

box elder, coast live oak, maple, liquidambar, coral, sycamore and many other species. Fusarium is a vascular clogging disease for which there is no cure.

The list goes on and on. Climate change and an ever more connected world will continue the trend toward future invasive erotic pests.

In early 2000, olive trees, (Olea europea) became very popular as a landscape tree, heavily planted throughout southland landscapes. For the past decade, olive trees have been declining from a number of diseases. Two of the diseases are fatal, both display similar symptoms, making diagnosis difficult.

Foliage display tip and marginal burn symptoms

Symptoms appears as leaf marginal burning, tip dieback, leaf scorch, and loss of foliage color. Defoliation proceeds from the top down and outside in toward the trunk. Small twigs die back, eventually larger branches and entire limbs die. Depending on location and season, the decline may be rapid or slowly over the years.

Xylella or Verticillium?

Disease Infection

Diseases known as quick decline, leaf scorch, or variegated chlorosis are caused by Xylella fastidiosa, the bacteria best known for causing Pierce’s disease on grapes, but also attacks citrus, peach, almonds, oleander, olives and many other species.
Verticillium wilt affects olive trees in commercial and landscape plantings and many other species. The disease is caused by soil-borne fungi, Verticillium albo-atrim and dahliae.

Both are vascular clogging diseases, where the fungus or bacteria spreads throughout the vascular system, restricting water movement within the xylem tissue. However, they have separate means of transmission. Unfortunately, neither disease has a cure, infected trees and shrubs decline over time, usually resulting in death.

Description and Spread

Xylella is transmitted by the glassy-winged sharpshooter, (Homalodisca vitripennis), leaf hoppers and spittle bugs. These vectors are xylem feeding insects.
The pathogen multiplies and spreads throughout the host tissue, restricting water movement through the xylem tissue.
Insect vectors feeding on infected trees (such as olive and oleander) may acquire the bacterium and carry it to new hosts.

Verticillium is a soil-borne fungus, it invades the root system of olives when the soil temperature is cool.

After penetrating through roots, the fungus multiplies within the xylem tissue, interrupting and reducing water movement from the roots to the leaves.
Each disease clogs the vascular system, interrupting water movement from the roots to the leaves.
Both diseases have similar symptoms making identification difficult.

Common Symptoms: (not all symptoms may be present)

Xylella:

Tip burn
Leaf scorch beginning at the tip toward the stem (petiole).
Marginal browning, scorch and yellowing.
Twigs and branches dieback beginning in the upper crown.
Desiccated leaf and fruit drop.
Production of suckers.
Crown dieback

Oleander infected with Xylella

Verticillium:

Symptoms appear in spring.
Newer leaves curl inward.
Dead fruit clusters remain attached.
Loss of leaf color and luster.
Leaf and fruit drop follow.
Inward leaf curl

Progressive decline

Dead fruit retained

Individual branches and or large portions of the tree may die within one season.
The tree may not die, growth may develop on unaffected portions of the tree and suckering from the crown.
The new growth continues until re-infected; the cycle repeats the following year.
Vascular staining
Vascular staining may be present.

Control

There is no cure for Xylella or Verticillium. Recommendations for both diseases include:

Remove suspected plants immediately to prevent vectoring disease to other susceptible host plants, i.e.: olive, oleander, sweetgum, grapes, etc.
Integrated pest management to control insect vectors may help slow disease spread but spraying to control leafhoppers is expensive and futile.
Control of nearby weeds and grasses to help limit insect vectors.
Pruning out infected limbs may improve the appearance, but it is impossible to prune “below” the infected wood, so pruning does not get rid of the disease.
Fungicide applications are not effective.
Remove declining and dead trees immediately.
Replant with disease resistant species.

Avoiding the disease is most effective but not always possible. Soils are easily contaminated with Verticillium from former planting and the pathogen may survive in the soil for several years, ready to infect newly planted susceptible species.

While greenhouse soils may be heat pasteurized to kill the fungus, that is impossible in the landscape. Solarizing landscape soils has some effect at reducing verticillium infected soils. Prior to planting, rototill and irrigate the soil as deeply as possible. Cover the area with six mil plastic, seal the edges with soils to secure for six to eight weeks.

Effective cultural practices such as fertilizer application, irrigation management, weed and insect control may assist in preventing infection and possibly reduce the effects of the disease. Most of these practices focus on improving plant vigor that help mask the disease, however these treatments are not curative.

It is important to note, many of the foliar symptoms described above may also be due to drought or poor irrigation practices. There are also foliar diseases that may produce similar symptoms but are only minor and may not pose a serious threat.

Diagnostic laboratory testing is the definitive method for a positive identification of the disease.

The important take away is this: Don’t ignore decline symptoms in olive and other susceptible species, as the plant may be infected with a fatal vascular disease. Declining and dead trees left in place may serve as a source for the disease to be vectored by beetles, sharpshooters and other pests to healthy nearby trees. Remove dead or dying trees to prevent disease spread.

Tree, Plant and Landscape Appraisals for Damages Caused by California Wildfires

Posted on December 3, 2018 by landscapeexpert

The Woolsey Fire

Once again, Californian’s throughout the state continue to suffer devastating losses due to wildfires. From the southland to northern California and the foothills of the sierra’s, the Woolsey, Camp, Hill and seemingly countless other fires have ravaged our state. From October through December, Santa Ana winds fan destructive blazes that grow in size with each passing year.

During recovery efforts, insurers and attorneys require a tree or landscape appraisal to settle a client claim. In the past year, RDCS provided appraisals for damages caused by the Thomas fire in Ventura and Santa Barbara counties, the Lilac fire in San Diego North county, the Liberty fire in Riverside County, Pocket fire in Geyserville, and the Erskine fire in Lake Isabella.

I recently published an article on the importance of specialized tree and plant appraisers for determining the cost and value of fire damaged trees, plants and landscape. Read the article Fire Damage & Tree Appraisal.

The Benefits of the ANSI A300 Tree Care Standards for Tree Related Lawsuits

Posted on January 18, 2018 by landscapeexpert

Guy + Chainsaw – Tree = Potential Lawsuit vs
ANSI A300 Tree Care Performance Standards

Does he know what he is doing?

Background

Tree care professionals contracting for services are frequently members of the Tree Care Industry Association, (TCIA). The International Society of Arboriculture, (ISA), administers various types of arborist certification programs, including certified arborist or certified tree worker climber. The American Society of Consulting Arborist offers arborists training and testing to become a registered consulting arborist, (RCA). These associations provide industry standards and best management practices for members to adopt into in their own practice.

Personal protective clothing, ropes, saddle etc.

In California, C-27 landscape contractors and D-49 tree service contractors are licensed by the state, both can legally perform tree care service. Prior to 1991, various industry associations, contractors and practitioners followed their own standards for tree care.

The industry recognized the need for a standardized, scientific approach and agreed to develop an official American National Standard, resulting in the American National Standards Institute (ANSI) A300 Tree Shrub, and Other Woody Plant Management Operations – Standard Practices.

They are voluntary industry consensus standards developed by TCIA and written by the Accredited Standards Committee (ASC) A300, whose mission is to develop consensus performance standards based on current research and sound practices for writing specifications to manage trees, shrubs, and other woody plants.

The ISA and ASCA are members of the ASC and their member practices should conform to the ANSI A300 tree care performance standards. The standards “apply to professionals who provide for, or supervise the management of trees, shrubs, and other woodsy landscape plants. Intended users include businesses, government agencies, property owners, property managers and utilities.” Many municipalities have adopted the ANSI A300 performance standards as part of their tree and landscape maintenance ordinance. The A300 standards are separated into 10 parts based on the tree care practice.

ANSI A300 Performance Standards for Legal Conflict Support

Arboriculture professionals adhere to the ANSI A300 performance standards for developing specifications for tree care. Gardeners, landscapers, designers, and handy men are not certified arborists and rarely have knowledge of industry standards. Even licensed landscape architects, civil engineers, general and landscape contractors may not be familiar with or have knowledge of the A300 standards. Ignorance of the standards is not a legal excuse for violating or ingnoring the standards.

The standards are separated into ten different parts. Through case experience, I have found three of the ANSI A300 standards applicable for plaintiff or defendant tree related legal actions. In conflicts I’ve been involved with, the civil engineer, landscape architects, general contractor, landscape and sub-contractors and even licensed tree care companies were not aware of the A300 standards. In some instances, industry professionals were aware of the standards but failed to adhere to the them.

Without proper planning and management, construction and development projects adjacent to existing trees commonly damage tree roots, trunks and limbs, increasing the risk of a potential tree failure and resultant lawsuit. ANSI A300 (Part 5) Standard Practices (Management of Trees and Shrubs During Site Planning, Site Development, and Construction) is the recognized industry standard for managing trees during construction and is the focus of this discussion.

The A300 Part 5 Performance Standard is intended for use for industry professionals, including all levels of government agencies, private entities including commercial, industrial and residential property owners and managers, engineers, architects and utilities for developing written specifications. The standards apply to any person or entity engaged in the management of trees, shrubs or other woody plants.

ANSI A300 Part 5 standard

Without specifications for tree protection during construction and development, tree injuries occur. Depending on the severity of the injury, the defect may degrade the structural integrity of the tree. Over time, the injury may continue to decay, increasing the risk of failure and resultant damage to people and or property. The reason for the standard is to assess the level of risk and to provide information for risk mitigation.

Civil engineers, landscape architects and other professionals responsible for developing plans and specifications should be aware of the A300 standards. These professionals may not have the tree knowledge expertise, which is why the standard refers professionals to use a certified arborist qualified in tree management during site planning, development and construction.

The standard discusses implementation procedures that should be designed by a professional arborist including:
• Tree management plans in compliance with applicable ordinances and standards.
• Decision making should be based on the knowledge of health and safety of the tree resources present.
• Prime consultant and contractor should involve the arborist in the initial planning phases.
• Arborist site monitoring during construction should be specified to ensure compliance with plan requirement.
• Monitoring specifications should address demolition, grading, vertical construction, walks and pathways, playgrounds, excavations, trenching, drainage systems, and landscape.

For safety, the standard requires only arborists familiar with the standards, practices and hazards of arboriculture shall perform tree management. One of the objectives of the standard it to avoid damaging trees during construction; including damage caused by physical contact, grade changes and soil compaction. To achieve the defined objectives on any project, the arborist should be involved in the management of trees during all five phases of development including:
• Planning
• Design
• Pre-construction
• Construction
• Post-construction

Development and construction projects are complex, requiring planning and coordination among project shareholders. The prime consultant and or contractor should maintain arborist involvement throughout the various phases of the project in conjunction with the arborist developing specifications, resource assessment, conservation plans, monitoring and recommendations. The TCIA website has an exhibit of a Tree management plan flow chart defining what should occur during the development phases, arborist responsibility and development activity.

How the A300 Standard Applies in a Legal Context

The standard applies to all design and planning professionals such as civil engineers and landscape architects. These firms usually work as prime consultants and are responsible for producing the plans and specifications for development projects. They are responsible for knowing and adhering to the A300 performance standards. The same applies to prime contractors and their sub-contractors, and other project stakeholders.

Failing adherence to the A300 standards renders prime consultant(s), general and sub-consultants potentially liable if a tree related accident occurs. I used the A300 standard in a case involving a tree limb that fell from a tree onto an adjacent tot-lot.

A city decided to build a park within a former old growth forest. A civil engineer and landscape architect developed plans and specifications, including a grading plan with notes and a detail for tree protection. The general contractor, grading, and recreation equipment sub-contractors constructed the park. The design included a tot-lot with children play equipment built where trees were removed, with old, construction damaged trees remaining left intact at the edge of the tot-lot.

A few days after the park opened, a tree limb dropped onto the tot-lot, striking and killing a young child seated on a piece of play equipment. The parents sued the city, the design consultants and all the contractors because the defendants did not observe the city tree ordinance. The city ordinance adopted the A300 tree care standards as part of their tree ordinance, which the defendants ignored, arguing the standard did not apply to their trade(s). After extensive deposition testimony, using the standards in support of the Plaintiffs (parents of the deceased child), all the defendants settled rather than proceeding with a trial.

In another case, a property owner agreed to allow a guy to prune a tree. The guy claimed to have forestry experience. He had a rope tied around a limb that he cut just as a neighbor walked out of their house. The limb dropped, rebounded at the end of the rope causing it to swing and strike the neighbor in the face. In the resulting lawsuit, the A300 standards were used to support the plaintiff complaint with a resultant settlement from the insurer.

The A300 standards apply to tree care companies, certified and consulting arborists. Different standards may apply depending on the case. For example, A300 (Part 9), Tree Risk Assessment A. Tree Failure, provides performance standards for tree risk assessment and guidelines for establishing written specification and best management practices, (BMP).

As a certified and registered consulting arborist, tree risk assessment inspections and reports are consulting services I provide, I’ve incorporated this and other standards into my practice. Tree care contractors might find other standards, such A300 (Part 1) Pruning, Part 5 (previously discussed) and Part 9 particularly applicable to their business.

In conclusion, the ANSI A300 Tree, Shrub, and Other Woody Plant Management Performance Standards are a powerful tool that may benefit a plaintiff or defendant involved in a tree related accident. The standards are broad reaching in scope and application to a wide variety of construction and development professionals. Attorneys and insures should consider the potential application of A300 performance standards in tree related cases.

Did You Take the Right Photo?

Posted on July 11, 2017 by landscapeexpert

I receive inquiries about tree failures from attorneys, insurers, HOA’s, commercial and residential property owners. Unfortunately, many inquiries concern a failure that already occurred, resulting in personal injury, property damage or both. Potential legal clients want to know the cause of the failure and whether the Owner or contractor satisfied the standard of care.

Forensic investigation to determine the cause of a tree failure may be difficult. Whether a limb or whole tree failure, the tree is usually removed and the accident site cleaned in a short period of time. Without actual evidence of the failed part to examine, determining the cause of the failure is impossible. Or is it?

If the Client took effective photographs of the tree failure at the time of the accident or shortly thereafter, a skilled arborist might be able to examine the failure for clues that could determine it’s cause. Unfortunately, most people take pictures that have limited or no value for forensic analysis.

Failure due to root disease. (Photo by JoeLaForest)

There are several types of failures to distinguish.

Root failures, usually due to a root rotting fungus, resulting in loss of anchorage, entire tree failure may occur, particularly during inclement weather. Blackened broken off roots may protrude out of grade.

Soil failure, the entire root ball rotates or heaves out of grade, typically occurs during wet, windy weather. In a soil failure, root protrusion from the soil mass is limited.

Soil failure resulted in tree loss.

Collar and basal stem injuries may result in the tree snapping off at the base. Collar injuries may occur from mechanical sources, such as string trimmers, mowers, or edgers. Trees grown in small, confined planters, such as cutouts in sidewalk may develop girdling roots resulting in poor root development and anchorage.

Restricted root zone results in collar failures

Within five years, tree trunk diameter may outgrow the opening within a tree grate. Construction activities that raise or lower the grade may also damage the root collar and surrounding surface roots.

Trunk failures may occur due to co-dominant trunks, two trunks of equal size sharing the same attachment. Co-dominant trunks may develop included bark, which weakens the trunk attachment, resulting in the trunk cracking or completing splitting apart along the weakened plane of included bark.

Co-dominant stems crack. (by Cherokee Tree Care).

Limb failures are perhaps the most common type of failure. Limbs may drop for a number of reasons. Typically, limbs fail due to weak attachments to the other larger limbs or the trunk. Multiple limbs attached at the same point, poor architecture, excess load, cracks, and cankers inevitably start to decay. As the decay decreases the structural stability of the attachment, the limb is susceptible to breakage or detachment from the tree, typically during inclement weather events.

Weak limb attachments. (by Randy Cyr)

However, sudden and summer limb drop are syndromes whereby healthy limb failure occurs during calm weather, usually May-October. The syndrome is still not fully understood or how to manage.

Although not a tree failure, surface roots may be responsible for damaging infrastructure, particularly lifting and cracking concrete sidewalks and patios, a major source of trip, slip and fall accidents.

Roots lifted sidewalk

Sidewalk replacement due to root damage

As roots age, they increase in diameter, just like a branch or trunk. As roots grow under a sidewalk age, they increase in diameter, slowing lifting sidewalk panels over time.

Trees typically fail suddenly,with little warning. The resulting impact may cause extraordinary property damage and possible personal injury or death. When an event occurs, emergency workers, media and the public are focused on the event, saving life or restoring traffic, not on taking forensic photographs of the accident.

Emergency crews at work. (by SD Union Tribune)

Forensic reconstruction of a tree failure relies upon factual evidence. If the failed tree or limb has been disposed, it is impossible to assess why the failure occurred unless well taken photographs exist. If a tree limb fell due to a cavity or defect, photographs showing the limb lying on the ground are of limited value.

Forensic photographs should depict the condition of the failed limb or whole tree. While a photo of the limb lying on the ground adds some context, it does not depict the cause of the failure.

Limb failed due to an old decaying canker.

Photographs should show the end of limb that broke off the tree and the scar or injury left on the tree trunk. Sometimes, it takes a long time for a limb canker to decay. Over time, the decay weakens the attachment of the limb which eventually fails. A photo showing the broken end of the limb and the damaged trunk area could prove invaluable.

Considerations for effective forensic tree failure photographs:

Timing:
- Take as soon as possible from date of the accident.
- Take photographs of changes in condition, ie: the tree stump remained one day but was removed a week later.
- If case extends over time, take photographs over the time period, this may help establish original tree wounds and healing rate.
- If using a digital device, turn on the date stamp for photographs.
Include Photographs of The Site:
- Establish the overall accident perspective with wide angle photographs depicting the entire site, street, park etc.
- Overhead or underground utilities, adjacent structures, construction activity.
- The presence of irrigation system.
- Damp, wet, moist, standing water conditions.
- Planter size, confined by curb, gutter, sidewalks, asphalt paving, driveways or other obstructions.
- Grade condition, accumulation of tree litter, mulch or compost placed around tree trunk and roots.
- Add a tape measure for scale
Include Photographs of the Subject Tree or Part:
- The entire tree or limb from one end to the other.
- Surrounding trees of same species for comparison.
- The broken end of the limb
- The torn, damaged area on the trunk the limb detached from.
- The root condition.
- The planter or turf area the tree was growing within.
- The soil conditions.
- Add tape measurements for scale and dimensions.

Tree failures occur infrequently, but when a failure occurs, consequences may be severe. The first reaction of emergency responders and the general public is to assist in an emergency, not document the cause. Since most tree failures are cleaned up and removed within a short period of time after the accident, valuable forensic evidence may be lost.

Photographs shown in this blog show the location of the failure, not the end result of the failure. Effective forensic photography should depict the failed tree component(s), including trunk scars, injuries, failed or torn limb ends. Tape measurements included in the photograph may prove very helpful.

When the tree or limb has been cut up and hauled to the landfill, the only effective evidence might be photographs taken at the time of the accident that depict defects that might establish the cause of a failure. An arborists requires evidence and facts to assess why a tree failed. Well taken photographs are often the most effective forensic tool available for analysis. So, take the right picture!