Trip, Slip and Fall Hazard: Hidden Depressions in Grade

Successful landscapes require:

  • Proper grading, drainage and amended soil.
  • An automatic irrigation system achieving 100% head to head coverage.
  • Properly installed, high quality plant material.

Each of these functions may require a specific type component, installed at a specific height or location to reduce the potential of creating a site hazard that may result in an accident.  In commercial applications, landscape plans usually include details and specifications dictating type of product and how it should be installed.

Many common landscape products may be improperly installed including:

  • Pop up heads may be incorrectly set to grade against a sidewalk.
  • Valve or drainage boxes set too high or low relative to finish grade.
  • Shrub head installed on a riser adjacent to concrete improvement.
  • Hidden, obscured depressions in grade due to substandard compaction, settlement and subsidence.

    Drainage box set too low.

Improper product selection or substandard installation practices may appear obvious.  A pop up sprinkler head set above the top of  adjacent concrete sidewalk creates a trip hazard.  A drainage structure set well below the turf grade creates a trip slip and fall hazard.  Selecting and installing a spray head on a rigid riser next to a pedestrian sidewalk is a sub-standard industry practice that creates a trip and fall hazard.

Spray head on a riser next to a sidewalk creates a trip hazard.

Not all landscape hazards are visible.  Turf areas may have grade depressions or holes that are hidden by overgrown turf grass.  Depending on the cause and time period, turf grass may completely hide the depth, location and size of the depression or hole, creating a hidden hazard.

A depression, rut or hole may result from several factors.  Repeated mowing on saturated turf may  create ruts.  Overwatering may cause irrigation or utility trench settlement.  A dead tree removed from a turf area may result in a future depression if the grade is not properly backfilled and compacted.

A seven inch deep hole hidden by turf grass.

Bermuda grass is a fast horizontal spreading turf-grass used in parks and recreation facilities throughout the country.  Unless regularly aerated and de-thatched, Bermuda grass in known to grow a  thick layer of thatch.  Over time, the thatch layer can increase the turf grade several inches above adjacent sidewalk and curbs.

The backfill in utility trenches installed across pre-existing turf may settle, creating a depression in the sub-grade.  The photo depicts the edge of a trench cut across an asphalt driveway, across a turf area.  The trench backfill eventually settled, creating a trench sub-grade depression hidden by the Bermuda grass.

Thatch, hidden depression and sanded turf.

The depression resulted in a trip and fall accident.  After the accident, several hidden turf depressions were “sanded” to fill  depressions to proper grade.

Not all landscape hazards are open and obvious.  Even a perfectly installed landscape may develop hazardous conditions if not regularly inspected and maintained.

Irrigation systems should be monitored, inspected, tested and adjusted monthly.  Turf should be trimmed around utility boxes and vaults regularly, aerated and de-thatched annually to maintain optimum performance and minimize grade changes.  Drainage structures should be grade adjusted, repaired or replaced when damaged.  Valve, electrical and junction boxes should be monitored for grade changes and adjusted as required.  Bark mulch thickness should be monitored and supplemented annually to maintain proper coverage and grade.

In summary, a properly installed landscape is composed of several systems and components that require regular ongoing maintenance for optimum performance, efficiency and safety.  Pro-active landscape maintenance may reduce potential hazards, resultant accidents and lawsuits.  These actions demonstrates an Owner’s recognition of protecting the health and safety of the public, pedestrians, friends and family who may visit and use the site and may prove useful in a legal action.

Old Growth Redwood Destruction Continues

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?

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

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

  1. 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.
  2. 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

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

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

Does he know what he is doing?

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.

Note the personal protective clothing, ropes, saddle etc.

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

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.

Landscape and Tree Contractors, Minimize Lawsuits, Understand Your Duty of Care!

If you are a landscape or tree care contractor, you should be aware of the potential liability you face by an unhappy client. This awareness begins when you understand your “duty of care” as a landscape or tree care professional.

What is “duty of care”? It is a very important legal concept that simply stated means a person or organization has the legal obligation to avoid acts or omissions that could harm others. The duty of care extends to your actions or lack of action that would cause harm to your client or their property, perhaps even extending to adjacent properties and utilities.

Licensed contractors should understand their client hired them for their expertise and professionalism. The client is reliant upon the contractor to provide a product and service that conforms to industry standards. It is incumbent upon the contractor to satisfy all contractual obligations and satisfy the industry standard of care, or face a possible lawsuit.

If you are a landscape, maintenance or tree contractor interested in learning how to minimize you legal exposure and reduce your liability, please read the full article at:

Reduce Liability by Understanding Your Duty of Care

Let it Burn or Suppress It? US Park Service vs Cal Fire Policy

This past summer brought us the gigantic Rim fire that devastated Yosemite National Park and surrounding communities. Over 4,900 firefighters operated under a unified command, however when the fire crossed over into the boundary between state and national park land, the National Park Service took a very different approach than Cal Fires (California Department of Forestry and Fire Protection). Continue reading “Let it Burn or Suppress It? US Park Service vs Cal Fire Policy” »

California Trees Under Attack, Are You Part of the Problem?

We have seen an increasing number of disease pathogens and insects attacking many tree species throughout our country.  In Southern California, the gold spotted oak borer, (GSOB), (Agrilus auroguttatu), first introduced in San Diego County between 1990-2000 has spread into Riverside County and is expected to spread throughout California.  This pest specifically targets the Coast Live Oak and Black Oak, (Quercus agrifolia, Quercus kelloggii), both oaks comprising a major part of our red oak forests throughout California.

GoldSpottedOakBorer, US Forest Service

The adult female beetle lays eggs on host trees mainly June through September, the eggs hatch into larvae which bore through the outer bark and feed on the phloem and xylem, the interior vascular system of the tree.  After several months, the larvae mature into pupae, which eventually bore from the vascular tissue just under the bark, and may be observed on the outer bark of infested trees April through July.  Adult emergence follows and the beetles feed on the foliage of the infected trees throughout summer, mating and then repeating the life cycle. Continue reading “California Trees Under Attack, Are You Part of the Problem?” »

The Pros and Cons When Using a Landscape Design-Build Contractor

Pros and Cons

Click Here to Download the PDF Version of This Article

This Post is Part Two of a Series, Click Here to Read Part One

In part one of the series Landscape Contractors Standard of Care, I discussed why a professional landscape contractor is held to a higher standard of care than an ordinary laymen. Wikipedia defines standard of care as “In certain industries and professions, the standard of care is determined by the standard that would be exercised by the reasonably prudent manufacturer of a product, or the reasonably prudent professional in that line of work.”

The previous article focused on primary contract documents required for professional landscape contractors and their clients. Contract documents focus on a design, plans, specifications, notes and details that provide the contractor information on how to price, bid, and construct a project. But what happens where there are no landscape plans or specifications for a project, no information is provided to the contractor to provide an accurate bid, quote or estimate and if awarded the contract, no information on how to construct the project? Continue reading “The Pros and Cons When Using a Landscape Design-Build Contractor” »