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.

Once Again, Fires Threaten Giant Sequoias

The Railroad fire broke out near Yosemite on August 29.  Recent humid, cooler weather has assisted fire crews achieve 43% containment, with 12,000 acre scorched.  However, dryer conditions are expected today, with the possibility of lightening strikes.

The fire is burning in an area of dry pine and cedar trees, creating difficult firefighting conditions.  Tuesday, the fire burned through Nelder Grove, containing over 100 mature giant sequoias.  Fortunately, the extremely thick bark protected the trees from damage, while all the under brush was burned.

Hopefully, firefighting crews can get the upper hand on the fire and prevent further damage.

Railroad Fire Threatens Giant Sequoias

Spring Madness

The beauty of spring is all around us, take a moment to enjoy it.  Take a walk through any of our coastal canyons, parks and open spaces.  You’ll be rewarded!

Not a field of poppies but still...

Not a field of poppies but still…

Wow

Wow

Get out there!

Get out there!

One of the Best Flowering Trees!

Back in my college days at Cal Poly Pomona, I took several plant identification courses as part of the educational requirements for Ornamental Horticulture.  Two trees from the same genus always stood out for their outstanding floral display and landscape use.  Back then, the genus was called Tabebuia, since changed to Handroanthus. The two useful landscape species are Handroanthus impetiginosa,(Pink trumpet tree) and H. chrysotrichus, (Golden trumpet tree).

The Pink trumpet tree in full bloom

While taking a walk, I came across a beautiful pink trumpet tree in full bloom.  I then started noticing a few other trumpet trees scattered about the neighborhoods in North Park.  I’m not to sure why, but in my view, this species is an under utilized ornamental landscape tree.  Perhaps due to a slow growth rate, medium appetite for water or its deciduous nature, the species is not heavily promoted by the nursery industry.  But it has many beneficial characteristics making it a useful ornamental landscape tree.

The pink trumpet tree requires full sunlight to part shade and grows to approximately 25-feet in height in Southern California.  The non-aggressive rooting system makes it a good choice for use in smaller confined planter areas such as a parkway strip.  It performs well in the urban environment.  Like most trees, it prefers well drained fertile soils however I see this tree flourishing under less than ideal conditions.  No noted pests or disease, hardy to 24º F, damaged below 18º F.  After spring flowering, it grows a green to brown colored pod.

A close relative to the pink trumpet tree but faster growing

A close relative to the pink trumpet tree but faster growing.  By M.Ritter, W. Mark, J. Reimer, C. Stubler

Unlike the pink trumpet tree, the closely relate golden trumpet tree is a more rapid, larger growing tree.  It too is deciduous, and like the pink trumpet, it flowers in the spring with an impressive display of brilliant, fragrant yellow trumpet flowers.

This tree grows to a larger size than the pink trumpet, up to 50-feet tall and similar width.  It has a spreading, low canopy that matures into a broad, round-headed or vase shaped crown.  It prefers full sun to part shade.

Branch strength is rated as medium to somewhat weak and root growth is more aggressive than the pink trumpet.  Unlike the pink trumpet, the golden trumpet tree should not be used in a confined planter are.

Both these trees perform well in our mediterranean climate and their different growth characteristics allow for varied use,  one in more confined areas, the other requires more room to grow.  Once established, both are relatively drought tolerant.

Hope you find this helpful, let me know if you have any questions!

 

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Worried About Your Tree?

We have gone from record drought to record amounts of snow and rain throughout California.  While the winter storms have wreaked havoc on our infra-structure (Oroville dam spillway, flooding in San Jose, etc, they have been a blessing for drought starved trees throughout the west.  Years of inadequate rainfall reduced soil moisture leading to an incredible dieback of trees numbering over tens of millions within the state.

The urban environment creates stresses not normally encountered in the wild.  In cities and suburbs, trees contend with confined planter area, compacted soils, improper or inadequate irrigation, poor maintenance practices, improper pruning, shading by homes or buildings.   Stresses created by the urban environment reduce tree life expectancy, sometimes by as much as 50%.

During the drought, I have seen an increase in tree failure, whether a limb drop or whole tree failure.  In most instances, crown, limbs, branch and twig dieback were the obvious symptoms of the drought.  Many times, clients mistakenly thought the dieback was caused by disease or insect, however root dieback from minimal soil moisture was the cause of crown dieback.

Now, with the heavy rainfall and wind, tree failure due to saturated soils are on the increase.  Trees remain upright due to their root system.  Structural and buttress roots grow outward from the trunk at the (root crown), out to the edge of the crown (known as the dripline).  At the dripline, the structural roots are 1-2″ in diameter.  They continue to grow outward, branching into the small, fine feeder roots that absorb moisture and nutrients.  Depending on local conditions, tree roots may extend 1.5 times the tree crown diameter.  Based on San Diego soil conditions, most roots grow within the upper three feet, typically 80% of the roots are within the top 18-24″ of the soil.

Roots in dry soil are held in place by friction.  However, when rain saturates the ground, it acts as a lubricant, lessening the soil friction holding roots in place.  When wind combines with excess weight from rain or snow, the energy is transmitted down the trunk to the roots.  Soil root friction reduced by saturation causes roots to loose anchorage, resulting in a failure.  When roots fail to support the tree, it is assessed as a root failure.  When the entire root ball rotates up from the soil, it is a soil failure.

Homeowners with large trees in close proximity to their property should examine their trees for any change in condition as a warning sign of a potential problem.  Changes to be aware of include:

  • Is the tree leaning?
  • Are there soil cracks at the base of the tree?
  • Is the soil lifting, tilting or rippling at the tree base?
  • Are there dead limbs or branches in the crown?
  • Is there a progression of twig, branch and limb dieback?
  • Did the tree drop it’s leaves abnormally early?
  • Did the tree not leaf out as in the past?
  • Any obvious open cavities, cracks or splits?
  • Any animals or insects nesting within a hollow, cavity or crack?
  • Any fluids, abnormal sap flow or other discharges from the tree?
  • Has irrigation been reduced or eliminated to the tree?
  • Has there been construction activity near the tree?
  • Have the roots been disturbed by any nearby utility or sidewalk work?
  • Is the tree sitting in water, is there proper drainage?
  • Has there been a change in grade near the tree?

If you can say yes to any of the above, your tree may have acquired defects that increase the risk of failure.  The increased risk of failure may result in property damage or personal injury to your family, friends, or any pedestrian near the tree.  A tree with a history of previous failures possesses an increased risk of failing.  Trees may not present any obvious signs or symptoms of a defect.  Unseen decay may exist within a limb or trunk, or as a root rot.

Whether commercial or residential property, if you are concerned about the health and safety of your trees, you should contact an arborist certified by the International Society of Arboriculture, (ISA).  Once certified, the ISA allows arborists to enroll in specialized training to earn the credential of a Tree Risk Assessor Qualified.  While anyone may attempt to assess the health and structural integrity of a tree, certified arborists who are qualified in tree risk assessment represent the industry standard and best management practice for tree risk assessment.

Tree risk assessment is the current best management practice to determine tree risk of failure associated with defects.  The assessment utilizes a level two basic visual assessment and a two page ISA format for the assessment protocol.  The assessor may determine more advanced assessment techniques are required, however usually a basic visual assessment will suffice.

If you have noticed a change in the health or condition of your tree, take proactive measures before a catastrophic accident, call a certified arborist knowledgeable in tree risk assessment.

Click here to read an article published in the LA Times Risk Assessment article.

Trees Damaging Los Angeles Infrastructure, Who Is Responsible for Liability and Repairs?

In May and June of 2015, The Los Angeles Times published articles addressing the problem of crumbling sidewalk infrastructure within the City of Los Angeles. The articles focused on the challenges pedestrians face in this car-dominated city. After years of mounting complaints and lawsuits caused by defective, dangerous sidewalks, city officials are finally beginning to address the problems caused by trees that were planted within city parkways, medians and right of ways.

Roots have damaged the sidewalk creating a trip and fall hazard

Roots have damaged the sidewalk creating a trip and fall hazard

After decades of deferred maintenance, the City Council, the Mayor, and public work officials are finally turning their attention toward addressing the problem, and trying to figure out how to juggle spending requirements resulting from legal settlements and sort out who is responsible for future sidewalk maintenance, as well as liability for future injuries caused by damaged sidewalks.

The first question, who is responsible for sidewalk repair and replacement caused by trees growing within city parkways and right of ways? California state law placed the burden of sidewalk repairs on adjacent property owners. A majority of California cities adhere to the state policy, however not the City of Los Angeles, which forty years ago opted for a policy that made the City responsible for repairing sidewalks damaged by tree roots in city parkways. Back in the 1970’s, when federal funding was available for the work, Los Angeles opted to pay for tree-damaged sidewalks. When the federal funding was depleted, voters declined to support tax increases for the repair work, leading to the current massive backlog of damaged sidewalks.

Instead of removing invasive, surface rooting tree species and replacing damaged sidewalks, the city embarked on a less expensive program of temporary asphalt patches in an attempt to smooth over displaced, uneven sidewalks. The problems continue to mount, with over 19,000 sidewalk complaints within the past five years alone. Over 40% of the complaints have been ignored, with no repairs having been made, mainly due to inspections never being made or the sidewalks so severely damaged they require complete rebuilding.

The City is now proposing a policy to address the situation. Under the proposed policy, neighborhood sidewalks damaged by city parkway trees would be replaced at the city’s expense. However, after repairs are completed, responsibility for repair, maintenance and liability would be shifted upon the adjacent property owner.

The proposal has received mixed comments from residential and commercial property owners. Businesses already pay taxes they assume local government should be using for infrastructure repairs. Additionally, requiring businesses to pay for repairs would harm retailers, especially in districts lined with problematics trees. Many commercial property owners would be forced to pass on the expense to the small business owners that rent the property.

Ficus roots creating a sidewalk hazard

Ficus roots creating a sidewalk hazard

Under the “fix and release” program, repairs would be made by the city, and then future responsibility for the sidewalks transferred to the homeowner. Some homeowners feel this would be an equitable solution to the current problem, other disagree, stating they would be saddled with big bills down the road, particularly if the city does not fix the “root” cause of the problem, that being tree roots or leaking utilities.

The city must grapple with both sides of a delicate issue, trying to preserve the benefits of large, picturesque trees providing neighborhood character while having to remove the same trees whose invasive roots have damaged infrastructure and would continue to do so if left in place. To begin the process, the city acknowledged they do not really know how extensive the problem is. The city has no existing tree inventory of the tree and sidewalk condition. Without this information, it would be difficult for the city to measure progress as they attempt to implement any new sidewalk management policy.

Certified and registered consulting arborists consult with Southern California municipalities and private property owners involved in trip and fall litigation caused by tree root lifted and damaged sidewalks. Typically lifted and damaged sidewalks caused by tree roots are due to inappropriate tree selection. Species such as Sycamore, Ficus, Eucalyptus and Ash trees planted decades ago in restricted parkway planters were most often associated with damaged infrastructure.

Sidewalk repair or replacement without addressing the existing tree species ignores the problem. Passing on responsibility for future repairs and liability to adjacent property owners would be an unjust situation for taxpayers. Large, surface rooting, invasive species should be closely examined for mitigation in conjunction with infrastructure replacement. Perhaps root pruning and root barriers might be an appropriate remediation that would protect future infrastructure while retaining large pre-existing species.

However, many species planted decades ago were and will always be inappropriate for confined parkways. Root pruning a large Ficus or Sycamore could easily de-stabilize the tree, resulting in a catastrophic failure. Who would be liable for a tree failure and resultant property damage, or worse, personal injury or death? Citizens might have to accept they cannot have the best of both worlds, where large, invasive trees are retained for neighborhood character, sidewalks are repaired and the city remains responsible.

Over the decades, many newer street tree species have been developed that provide desirable growth characteristics while minimizing damaging invasive root systems and towering canopies that conflict with traffic and overhead utilities. Reasonable compromises can and should be made toward replacing older, inappropriate tree species with newer species that will provide community benefits while minimizing maintenance costs and damaged infrastructure.

Hopefully, the City of Los Angeles and other municipalities facing this problem elect to use certified and registered consulting arborist and horticulturists as they consider how to address their urban forest and infrastructure issues.

To read the full Los Angeles Times Article, click the link:

L.A. Considers Shifting Responsibility to Property Owners

 

Removing Your Turf and Sprinklers Due to Drought, Remember the Trees!

As Californians scramble to find a way to reduce water consumption to meet a 25% water reduction mandate, turf removal has become the latest means to accomplish significant water savings. From Santa Barbara to San Diego, with Los Angeles and Orange county in between, turf is being ripped out at a frenzied pace.

Considering the rebates offered by the Metropolitan Water District in Los Angeles and other municipalities, homeowners and businesses are jumping at the opportunity to be reimbursed for turf and spray irrigation removal.  Succulent gardens, Mediterranean, and California natives and other drought tolerant plant materials are being used to replace water guzzling turf.

The decades long love affair with our green turf lawns is coming to an end.  Unless you can afford to pay extremely onerous penalties for excessive water use, the California drought, climate change and dwindling water resources will change the way we design, plant, irrigate and use our landscaped areas.

As turf and spray irrigation is removed, it is easy to forget about trees in the landscape. Trees planted in the landscape rarely receive irrigation dedicated to just the tree.  Typically, the tree is located in an irrigated turf or planter area.  Tree roots grow where there is moisture.  Trees adjacent to an irrigated turf area will certainly root into the turf zone because that is where the water and nutrients are.

A common misconception is trees develop deep tap roots that grow deeply into the soil to locate water.  In fact, almost all tree roots grow within the top three feet of the soil mass, almost 80% of the roots grow within 12-24 inches from the soil surface!  Initially, a tap root growing downward will encounter rocks, hard pan or other physical impediments causing the tap root to split into a fibrous system growing horizontally through the soil profile.

As roots grow outward from the trunk, the tree crown grows in conjunction with the spreading root system.  The outward edge of the tree crown is referred to as the drip line of the tree.  The structural tree roots grow outward toward the drip line, however they don’t stop there! Outside of the drip line, the structural roots become increasingly smaller in diameter and that is where the fine absorbing root hairs are located, often well outside of the tree drip line.  Many tree species grow roots up to twice the tree crown diameter!

Knowing how tree roots grow is vital to understanding how your trees will react to changes in irrigation caused by converting turf or high water use areas.  If the edge of a tree crown or drip line is near an irrigated turf area, it most certainly will have rooted into the turf soil zone.  When the turf is gone and water is turned off, the tree will have lost it’s primary source of water and nutrients and will begin to decline.  If it does not have or develop other water resources to tap into, the tree will eventually die.

If you notice the crown of your trees declining, not leafing out or new buds dying back, these are symptoms that may be caused by the affects of drought or lack of water. Think back and consider what changes have occurred in the past one to two years? Has there been construction or renovation work nearby?  What about changes in the landscape, was the turf removed and sprinklers turned off?  Was there trenching, rototilling or soil preparation in an area nearby existing trees?

You can still remove your water consuming turf and use drip irrigation, just remember to plan for irrigating the trees.  If using a drip system, consider using higher volume emitters, or other distribution systems that will provide an adequate water supply to the tree. Add a drip valve solely dedicated to tree irrigation separate from the other shrubs or ground covers.  Proper planning, installation and maintenance is required to convert water consuming landscapes into sustainable, water efficient landscapes while preserving existing tree health and aesthetics.

With proper planning, trees can be grown and will flourish using drip or low volume irrigation systems but you must provide enough water distribution to encourage the tree to root into the surrounding site soil.  Unlike spray irrigation, drip systems must be maintained and upgraded as trees grow larger root systems.  Additional drippers or emitters are required as the tree crown increases in diameter.  Drip and low volume distribution systems work great but are more labor intensive than spray systems and require a higher degree of maintenance.

So go ahead and get rid of that old ugly bermuda grass lawn, or grit your teeth and say goodbye to your green lush tall fescue or Kentucky bluegrass and say hello to water savings without sacrificing visual aesthetics.  You can keep your trees alive and flourishing while still achieve water savings and a unique, beautiful landscape.  Use a landscape and certified arborist tree professional to help you achieve your sustainable, affordable landscape!

 

 

Red Trees = Dead Trees in California National Forest Lands

I recently read an article in the Los Angeles Times Drought Trees 1 , Drought Trees that addressed the tremendous die-off of trees within California’s national forests.  The aerial pictures in the article depict vast areas of red colored trees dominating the forest land.  As the drought continues, the death toll on our national forest lands is approaching record numbers.

To date, scientists and U.S. Forest Service representatives estimate at least 12.5 million trees in California’s national forest have been killed due to drought. Unfortunately, scientists expect the die-off to continue as the state heads into the summer season, traditionally the driest months of the season and the months with the greatest fire threat. The last time researchers saw such a great die-off was during the drought period of 1975-1979, when an estimated 14 million trees died.

As a professional arborist, horticulturist and outdoor enthusiast, I find it incredibly sad and painful as we helplessly watch millions of trees die in our forest lands.  Since childhood, I have loved camping throughout California, whether in the local San Diego mountains, the Sierras, or coastal California, the common denominator was the presence of trees, sometimes big trees.  Oaks, pines, sycamores, redwoods, cedars, the list goes on, so many beautiful tree species whose survival is now being threatened by drought.

I first became aware of the effect of the drought on client trees two years ago and the problems have only increased in the urban forest and wild land trees.  Oaks, pines and peppers on non-irrigated lands that survived for decades are now finally succumbing to the drought.  The grinding, relentless drought has reached a point where water tables and soil moisture are too depleted for many trees to survive. Clients have called with questions why trees they have in the past ignored are now declining.  Non-irrigated trees located in slopes or non-viewed areas that survived and flourished for decades are now in decline or dead.  As turf irrigation is turned off trees decline and die.

Trees weakened by drought are being infested and killed by wood boring beetles.There has been an uptick in the beetle populations due to the dry drought conditions. A healthy tree exerts internal pressure and pushes sap out of the tree surface, in effect forcing intruders out of the tree.  But when a tree is dried up, it cannot develop the sap flow and other natural defenses to ward off the wood boring insects. Trees weakened by drought become susceptible to invasion and colonization by beetles, killing the host then spreading to other weakened or even healthy trees.

As trees die-off from drought or killed off by beetles, millions of dead trees increase the likelihood of devastating summer wildfires.  San Diego county has suffered some of largest wildfires in the state. Decades ago, I used to take my family to campgrounds in the Cuyumaca and Laguna mountains that were later destroyed in the Cedar and Witch fires back in 2003-2005.  Even now, the standing dead, blackened, trees are a reminder of the terrible results of wild land fires.

In the past, “normal” spring weather resulted in green hillsides and mountains, with wildflowers and snowcapped peaks.  That has not been reality for the past several years. Anyone can easily see the already brown, grey hillsides, it looks like the middle of the summer yet it is only May.  The small amount of rain this past weekend, while a wonderful event, two days later you would never know it rained at all.

I have no recollection of the drought in the late seventies.  I was a college student back then and drought was not something that registered on my horizon at the time.  Now, after decades working in the landscape, arboriculture, horticulture and land development industries, this drought is frighteningly real and showing no signs of relenting.  Mandatory water restrictions are affecting the lives of all Californians.

The real scary question for me, is this our new climate?  I don’t want to see a California devoid of redwoods, oaks, sycamores and so many species I have grown up with and grown to love.  Regardless of how much water we conserve, the trees in our forest lands are at the mercy of mother nature.  The drought of the seventies killed millions of trees but that drought ended and millions of trees recovered and flourished.  Lets hope for a similar scenario with the current drought and tree die back.

Read the full Los Angeles Times article at Drought Trees 1Drought Trees

Reducing Irrigation During the Drought? Don’t Forget Your Trees!

I have been getting an increased number of calls from people concerned about their tree(s) starting to dieback. They want a certified or registered consulting arborist to evaluate the tree health condition, determine the cause of the tree decline, and recommend treatment options or removal.

For the past two to three years, I have noticed the increasing number of declining trees throughout San Diego. Especially noticeable is the tree dieback in the backcountry as well as local canyons and open spaces. Even drought tolerant Eucalyptus, Oak and Pines trees are struggling to survive.

The cause of our tree decline and dieback is the ongoing California drought. With yet another year of little winter rain, soils throughout San Diego county have little moisture reserve remaining. The drought is affecting native as well as ornamental trees used in the landscape.

Indeed, certain trees in our area are struggling due to insect infestation. The gold spotted oak borer attacking Coast Live Oak, as well as a host of ornamentals including Olive and Liquidambar trees have been infected with fusarium vascular disease introduced from borer and insect infestations. Therefore, it is not uncommon for most people to assume their tree must be declining due to some kind of insect or disease.

I have observed people rarely consider the effect of the drought as being the primary cause for tree decline. The tree living in the back yard or slope area for the past several decades may be dying simply because there is no more water in the soil profile!  Even the deepest rooted trees cannot survive accumulated years of consecutive drought.

I recently received a call from a gentleman complaining his fifty year old Jacaranda tree was dying. The new foliage had germinated then died back, now small twigs and branches were dropping. The bark on the trunk was exhibiting uncharacteristic roughening. The tree was located at the bottom of a slope near a turf area. Months ago, the turf sprinklers had been turned off, now the tree was struggling to survive.

Tree roots seeking moisture grow well beyond the drip line of the tree crown. Under drought conditions, soil moisture is not being recharged from winter rains. Unless a tree is receiving supplemental irrigation, it is reliant upon finding soil moisture by growing into irrigated turf and planter areas.

With increased water restrictions and rates, people are reducing or eliminating irrigation to their lawns and shrub beds without considering the effect on nearby trees. Trees that adapted their root systems to getting water from nearby irrigated areas that no longer get watered will begin to decline as the remaining soil moisture is exhausted.

A tree weakened by drought becomes increasingly susceptible to secondary pest or disease infestations. Many beetles can detect stressed trees from miles away. However, attempts to eradicate secondary insect infestations will not resolve the underlying cause of the tree decline.

So, if you notice your tree starting to decline, here is a brief check list of considerations:

-Is the tree irrigated or non-irrigated?
-If non-irrigated, does the tree get water from a nearby irrigated source?
-Has there been recent re-programming or turning off the irrigation?
-Any recent construction or trenching nearby the tree?
-Any grade change such as fill soils placed over the tree roots or cuts?

A well maintained, mature street tree in the front yard of a property may add an additional 7% to the assessed value of a property, a dead or declining tree obviously reduces street appeal and real estate value.  Trees can be retained and successfully survive the ongoing drought, contact a certified or registered consulting arborist to provide a tree health evaluation and recommendations on how to protect your tree investment value.