Our projects range from small privately held properties to designing specifications for large public agencies to evaluate and manage their urban forest.

Golf course tree management

Irrigation with recycled and desalinated water

Landscape planting and management

Plant problem diagnosis

Site analysis and plant selection

Tree Appraisal

Tree preservation

Tree risk assessment

Training, education,and research

Urban forest management

Tree Preservation



Doyle Dr. Replacement, San Francisco

HortScience provided consulting servicesa for Caltrans and the Presidio Trust to identify impacts to trees that would be affected by the new Doyle Dr. alignment.  We inspected the adjacent vegetation and identified trees for preservation, pruing or removal.  We also provided tree protection guidelines for Caltrans and its subcontractors working around trees.


John Muir Medical Center. Walnut Creek, CA

HortScience worked with Gates and Associates, the project landscape architect, to assess over 400 trees at the site, evaluate impacts from the proposed construction and assess trees for transplanting.  We provided specifications for tree protection and transplanting, and monitored construction activities near trees.


BH Development. Walnut Creek, CA

HortScience was the project arborist for the Oak Lane project. A mature valley oak was the project's focal point. Demolition of multi-story structures within the tree's dripline was followed by construction of new facilities also in close proximity. We attended public meetings as part of the design phase. We continue to provide tree management consultation.


The O'Brien Group. San Mateo, CA

HortScience was the project arborist for the Vintage Oak project in Menlo Park. We prepared the initial resource evaluation, worked with the design team to minimize impacts from construction, prepared tree protection specifications, and monitored tree preservation during construction, This project received an award for its tree preservation program from the National Arborist Association.


SummerHill Homes. Palo Alto, CA

HortScience has provided consultation services to SummerHill Homes during the design and construction phase for over 20 residential projects in the SF Bay area. We responded to the varied tree preservation and reporting requirements of communities in which the projects were constructed.


City of Brentwood, CA

HortScience worked with City staff and LPA Associate from conceptual phase through construction documents for the redevelopment of their Civic Center/City Park.  We prepared a tree report for 86 trees located in City Park and adjacent to existing city buildings. We participated in design decisions to reduce impacts to trees, prepared tree preservation guidelines and provided specifications for transplanting mature Southern live oak trees.  


City of Hayward, CA 

HortScience worked with the City and its contractor in sidewalk, curb, and gutter replacement program. We assessed tree condition, suggested design alternatives, and guided root pruning operations. The goal was to minimize root loss and tree removal while maintaining tree stability and public safety. We provided specifications for tree protection and root pruning, and monitored construction activities near trees.


City of Palo Alto, CA

HortScience was the contract arborist representing the City of Palo Alto for improvements to Stanford Shopping Center, the Sand Hill Road extension and widening, and design and construction of the Stanford West Apartments. We were responsible for plan review, construction monitoring, and documenting tree health over a 4-year period.


East Bay Municipal District. Oakland, CA

HortScience provided consultation on tree preservation during design and construction phases of the San Ramon Valley Transmission Improvement project. This 69" pipeline was installed over several miles of existing trail, park and roadway. Our work included tree survey and assessment, evaluation of plans, recommendations for design modification, construction monitoring, and public outreach.


<return to top>


Tree Risk Assessment



City of Santa Monica, CA

HortScience assessed over 600 carob trees along streets and in parks for the City’s Open Space Management Division. The assessment had two goals: 1) to identify trees in danger of failing and 2) to recommend treatments that would reduce the risk posed by trees. We performed a visual inspection, rated the risk, and recommended action to manage risk of tree failure. We also participated in public meetings regarding risk reduction, tree removal, and replacement.


East Bay Regional Park District. Oakland, CA

The East Bay Regional Park District comprises some 65 parks encompassing 98,000 acres.  Parks range in location from urban to semi-rural; in forest cover from completely planted to native woodlands.  HortScience assisted the District to develop a tree hazard inspection and assessment program including a revision to the Park Operations Manual section dealing with tree hazard assessment. We  continue to provide training workshops and follow-up assessments of hazard inspections.  Over time, our role has evolved to include tree selection and general management.


County of Santa Clara, CA

HortScience performed an assessment of 17 campgrounds and picnic areas in Mount Madonna Park, one of the County’s facilities.  We visually assessed each tree in the park’s use areas.  Trees with significant defects were tagged, assessed, and rated for hazard using the 12-point rating system.  Priorities for action to abate hazards were provided based on the hazard ratings.


City of San Francisco, CA

The City's Recreation and Park Department contracted with HortScience to evaluate the health, structural condition, performance and risk associated with over 1,000 trees along Park Presidio Blvd., in the area between Golden Gate Park and the Presidio. We attended public meetings to respond to questions.


San Francisco State University. San Francisco, CA   

HortScience was retained by San Francisco State University in 2004 and 2008 to provide management recommendations for the nearly 1,100 mature trees located at the SFSU campus.  HortScience collected data on species, trunk diameter, and health and condition, as well as hazard.  Management recommendations included pruning, cabling/bracing and removal to abate risk.  Species age and performance data were also used to help guide species selection for future reforestation.


The Presidio Trust. San Francisco, CA

The Presidio of San Francisco comprises 1,500 acres and an estimated 60,000 to 70,000 trees. In 2003 and 20054, HortScience evaluated the hazard associated with approximately 6,600 trees. We recorded information about the species, trunk diameter, and condition as well as specific details such as tree structural defects and pests or diseases, and rated the hazard.  In 2009 we reassessed the trees, adding another 1,200 trees to the database and updating the database.


<return to top>


Urban Forest Management



City of Palo Alto, CA

HortScience is preparing an urban forest plan for the City of Palo Alto.  The project will focus on sustainability and employ the model developed by Jim Clark and Nelda Matheny in the late 1990s.  Another key feature is the creation of protocols designed to help City departments communicate about tree management.  The project is beginning with an online survey of the community and stakeholders, followed by a study session with the City Council.


City of Piedmont, CA

HortScience provides on-call consulting services to the City of Piedmont, most often related to the management of the City's street and park trees. We have prepared assessments of tree health and structural condition, appraisal of value, assisted with tree preservation during construction as well as provided testimony to the Park Commission.


City of Pleasanton, CA

HortScience provides on-call consulting service to the City of Pleasanton, most often related to the management of the City's Heritage trees. We have prepared assessments of tree health and structural condition, appraisal of value, assisted with tree preservation during construction.


Friends of the Urban Forest. San Francisco, CA

HortScience worked with the non-profit group Friends of the Urban Forest to assess the state of San Francisco's Urban Forest.  We met with the stakeholders, identified a series of management principles, and determined challenges of managing a largely planted urban forest.  This project led to development of an Urban Forest Master Plan for the City.  Working closely with San Francisco's Urban Forests Council, we clarified goals and developed a plan to meet detailed objectives.


National Park Service. Sausalito, CA

HortScience assessed the condition of stands of trees that are in the National Historic Register at Fort Baker, part of the Golden Gate National recreation Area, to determine how to sustain their structure and integrity near the end of their life span.  We provided tree stand risk assessments, tree protection during construction advice, and replanting recommendations.


Golden Gateway Center. San Francisco, CA

Golden Gateway is responsible for the management of the landscape in the Sydney Walton Square.  HortScience has been hired annually since 2001 to assess the health and structural condition of the trees in the square and to provide a risk assessment.  Management recommendations included pruning and removal to abate hazards and improve public safety, as well as to mitigate the loss of mature Monterey pine trees to pine pitch canker.


University of California. San Francisco, CA

HortScience prepared a Vegetation Management Plan for 61-acre Mt. Sutro Open Space Reserve.  Consultation services included a field survey of tree health and structure, and forest composition.  We developed management plans to achieve six possible outcomes.  HortScience coordinated this project with three subcontractors and interacted with a University steering committee and public interest group.


Presidio Trust. San Francisco, CA

The Presidio Trust manages several groups of trees designated as Historic Forest. These areas are one of the defining features of the site. HortScience was retained by the Trust to provide management recommendations and specific forest treatments within the framework of the regulatory mandates of the National Historic Landmark Designation. HortScience worked closely with the Trust and the historian to identify historic strands and their contributing features. We provided clear management recommendations to protect historic features and promote tree health.


City of Long Beach, CA

HortScience worked with Melendrez, a planning and design firm, to assist the City in developing Phase 1 of an Urban Forest Master Plan.  The team interviewed stakeholders including elected officials and public agencies, and identified 7 goals for the community to address.


City of Redwood City, CA

HortScience assisted Redwood City's Street Tree Policy Task Force in addressing the city's tree —pavement conflicts.  To begin, we surveyed existing programs throughout the U.S., Canada, and Europe to identify innovative design and management solutions.  Next, we helped the Task Force refine explicit goal statements and produced a technical document that has been adopted into a new sidewalk repair policy.





<return to top>


Golf Course Tree Management



Blackhawk Country Club. Danville, CA

HortScience teamed with a golf course architect to provide a tree management plan for the Club's 36-hole golf course.  We consulted on the management of individual trees and groups on an on-call basis. The trees included large over mature blue gum eucalyptus.


Del Rio Golf & Country Club. Modesto CA

Del Rio's 27 holes of golf are located in native oak woodland and riparian corridors.  A wide range of tree species was planted when the Club was developed in the 1930s.  HortScience assessed the health and structural condition of native and planted trees, and prioritized recommended tree care activities.  We prepared a palette of tree species suitable for use in a variety of maintenance settings within the golf and country club.


Presidio Golf Course. San Francisco CA

The Presidio Golf Course is managed by Arnold Palmer Golf Management and is required to have an assessment of tree health, structural stability and risk performed every two years.  We've worked with course staff to provide the assessment and recommendations for abatement and tree management.


Ruby Hills Golf Club. Pleasanton CA

HortScience has been involved with the Nicklaus Sierra/Signature Properties course at Ruby Hill in Pleasanton since the initial planning phase in the early 1990's.  We assessed the tree resource during the design stage, monitored preservation measures during construction, and provide on-going consultation as the trees mature. 


The Olympic Club. San Francisco CA

At The Olympic Club's 45-hole golf facility in San Francisco, we prepared a comprehensive Tree Management Plan.  We assessed the health and structure of over 500 key trees and prioritized recommendations for removal, pruning, and other maintenance activities.  We prepared a palette of trees suitable for planting, and then worked with the superintendent to integrate new plantings into overall course management.


The Richmond Country Club. Richmond CA

At the Richmond Country Club, HortScience performed a census of nearly 3,000 trees in stands and 40 prominent trees.  We prepared a comprehensive Tree Management Plan, including identification and prioritization of trees recommended for removal, pruning, and other maintenance activities.  We created a palette of trees suitable for planting, and then worked closely with the superintendent to integrate new plantings into overall course management goals and priorities.


<return to top>


Landscape Planting and Management



Lennar Communities and Shapell Homes. San Ramon, CA

HortScience developed plant quality criteria for new landscape installation at the Gale Ranch and Windemere communities in the City of San Ramon’s Dougherty Valley planning area. Our quality criteria were accepted by City and County inspectors, developers, landscape contractors and wholesale nurseries.  Over a period of 8 years, HortScience inspected plant materials delivered to the new project sites to evaluate plant quality prior to planting.  In some cases we identified acceptable stock at wholesale nurseries prior to shipping   Our work facilitated acceptance by City inspectors, and enhanced landscape appearance and performance.


National Park Service. Sonoma County, CA
HortScience assisted landscape architect Pattillo and Garrett by conducting an assessment of the historic landscape at Jack London State Park.  We evaluated both native and introduced trees planted by Jack London to assess their condition, potential longevity, and landscape significance.  This work was done as part of our contract with NPS Pacific West Regional Office and WJE Associates, Inc. to provide horticultural consultation for historic preservation of parks in the Western region.
Alameda County Waste Management Authority. Oakland, CA

Under contract with the Authority’s (, HortScience developed the Model Bay Friendly Landscape Maintenance Specifications.  The goal of the Bay Friendly Landscaping effort is to perpetuate the environmental and biological health of the San Francisco Bay.  The specifications describe practices and materials to maintain landscapes in an environmentally sensitive manner.


<return to top>


Site and Plant Selection



SWA Group. Sausilito, CA 

Mountain House is a planned community in Tracy area. At completion, it will provide homes in 15 neighborhoods, schools, parks and commercial facility to 45,000 residents.  HortScience consulted on  master plan with the landscape architect by providing site evaluation and plant palette, Inc. review.  We also provided tree preservation expertise where mature trees were present in new project areas.
John Nicol and Associates. Walnut Creek, CA. 
John Nicol and Associates was the landscape architect for the Windemere project in San Ramon CA.  This master planned community includes 50 villages, 18 parks, 4 schools and many miles of streets.  HortScience  worked with John Nicol as well as the developer and landscape contractor. HortScience evaluated site conditions and advised on plant selection over the last ten years. We collected soil samples, evaluated the site conditions, prepared pre-planting soil amendment specifications, and reviewed proposed plant palettes for suitability to the site as each component was designed.  In addition, where recycled water will eventually be applied, we advised about appropriate plant selection and management.
NUVIS, San Ramon, CA
Dublin Ranch is master planned community in Dublin, CA, developed by Shea Homes and built by Standard Pacific, Toll Brothers, Centex, Brookfield and Shea Homes, among others. HortScience worked with landscape architect NUVIS to evaluate site and soil conditions and identify appropriate plant species that would tolerate the site’s alkaline, calcareous soils and irrigation with recycled water. 


<return to top>


Recycled and Desalinated Water for Irrigation



City of Palo Alto. CA

The Mountain View Recycled Water Project is Phase 2 of the City of Palo Alto Water Reuse Program which provides recycled water to the Shoreline area of Mountain View.  In 2005 HortScience and Kelley & Associates Environmental Sciences evaluated landscapes in that area, investigated soil conditions, and determined plant species response to irrigation with recycled water.

In 2009 we established monitoring stations to assess any changes to soil chemistry or plant condition that may occur when irrigation is changed from potable to recycled water.  Under contract with Thomas Barron, C.E., we installed soil moisture measuring and recording devices, established a program of routine soil and plant tissue sampling, and developed a plant appearance rating system.  We are currently establishing baseline information while the landscapes are being irrigated with potable water.  Landscape irrigation was converted to recycled water in early 2010; monitoring will continue for several years.

Palo Alto Recycled Water Project is Phase 3 of the City of Palo Alto Water Reuse Program that will distribute recycled water from the Regional Water Quality Control Plant.  Under contract with RMC Water and Environment who is preparing an Environmental Impact Report for the project, HortScience and Kelley & Associates Environmental Sciences are evaluating sites in the Stanford Research Park area in which recycled water will be available for landscape irrigation.

Our work includes examining soil profiles, analyzing soil chemical properties, measuring soil infiltration rates, and identifying landscape plant species and ranking their salt tolerance.  Using site-specific information, we will evaluate the effects prolonged irrigation with recycled water will have on the health, function, and appearance of those landscapes.


City of Redwood City. CA

In 2002 HortScience provided an informational presentation to the City Council regarding possible effects of recycled water on existing landscapes, and factors that should be considered before conversion from irrigation with potable water.  Currently we are evaluating the site conditions at properties in the Redwood Shores area where recycled water is already being applied, as well as at properties that will be converted in the future.  The assessments included extensive soils investigation, examining the soil profile to four feet depth, and analyzing chemical characteristics and texture.  We are in the process of developing a pilot study to monitor the response of Lombardy poplar trees at Oracle's headquarters to irrigation with recycled and potable water.

Poseidon Resources. Stamford CT.
The City of Carlsbad CA is planning to construct a desalinization plant. The City was concerned about the potential for desalinated water to negatively affect landscapes within the community.  Under contract with Poseidon Resources, we approached this problem by inventorying landscapes throughout the city to identify common landscape species, analyzing performance of those species in other cities where landscapes were irrigated with desalinated water, and performing soil, tissue, and water analyses to quantify plant salt tolerance.  At the end of the project we provided Carlsbad staff with the information they needed to fully assess how their landscapes would change when using desalinated water.
Santa Clara Valley Water Agency. San Jose, CA.

HortScience conducted the site evaluation phase of a research project to investigate the cause of decline of mature redwood trees in Santa Clara, San Jose, and Milpitas.  Trees were irrigated with recycled water.  We described site and tree characteristics at each of six study locations, and collected plant tissue, soil, and water samples for laboratory analysis.


Stanford University. Palo Alto, CA

Managers of the 700-acre Stanford Research Park were concerned about the effects irrigation with recycled water would have on their landscapes.  HortScience evaluated site conditions and prepared recommendations for appropriate water quality to maintain landscape function and appearance.


<return to top>


Training Education Research



Tree hazard assessment training. East Bay Municipal Park District. Oakland, CA

HortScience provides training to the District’s supervisor and rangers to familiarize them with the organization’s tree hazard assessment program. HortScience prepared the training workbook and developed the workshop outline. Workshops consist of both classroom and field sessions.

Tree risk assessment training. City of Milwaukee WI
The City’s Bureau of Forestry retained HortScience to develop and implement a training program for its arboriculture and urban forestry staff. Training consisted of classroom and field sessions dealing with the identification of structural defects and their management.
Literature Review:  Tree pruning. International Society of Arboriculture
HortScience reviewed the arboriculture and urban forestry literature for research on the topic of tree pruning, emphasizing mature trees.  192 citations were evaluated, annotated and organized by topic into a searchable database.  A summary article is available through the Publications page.
Literature Review:  Tree risk assessment. International Society of Arboriculture
HortScience reviewed the arboriculture, urban forestry, and forestry literature for research on the topic of tree risk assessment, emphasizing mature trees.  Over 800 citations were evaluated and organized by topic into a searchable database.  A summary article is available through the Publications page.
Model for Urban Forest Sustainability, USDA Forest Service.
With the U.S. Conference of Mayors and California ReLeaf as its partners, HortScience addressed the question: what makes a community's urban forests sustainable?  With funding from the USDA Forest Service, we conceived, developed, and evaluated a series of criteria and performance indicators for urban forest sustainability.  Our efforts resulted in several publications, training sessions, and presentations.  We applied the model to the urban forests in 25 cities in the U.S. Summary articles are available through the Publications page. More importantly, the model has been adapted and utilized by communities.  The Sacramento Tree Foundation's Greenprint program ( builds upon our model.
Sycamore Grove Park. Livermore Area Recreation and Park District.
HortScience worked with the Park District and local water agency Zone 7 to evaluate the factors affecting the decline of one of the largest remaining stand of sycamores in California.  We participated on an inter-disciplinary team to determine how the even-aged stand of trees might be managed to enhance longevity and produce a new generation of trees. The research components included tree condition, dendrochrology, genetic composition, hydrology, and soils, as well as climate, canopy cover, and geomorphic changes since construction of the upstream dam.
A National Research Plan 2005 - 2015 for Urban Forestry. USDA Forest Service.
HortScience worked with the Aslan Group and the University of Washington to develop a National Research Plan for the USDA Forest Service Research in the area of urban and community forestry. A summary article is available through the Publications page.
Assessment of the USDA Forest Service Urban and Community Forestry Program. USDA Forest Service.

HortScience worked with the Aslan Group to 1) create a database of existing urban and community forestry programs in the U.S. and 2) assess the federal program.  A project of the National Urban and Community Forestry Advisory Council. A summary article is available through the Publications page.


<return to top>


Tree and Landscape Appraisal

City of Pleasanton, CA
The City has retained HortScience to provide an appraisal of tree value on a number of occasions. In some cases, residents have illegally removed City owned trees. In others, City-designated Heritage trees have been damaged or removed. HortScience employed the standard methods of tree and landscape appraisal to provide assessments of value.
City of San Mateo, CA.
San Mateo requires that all development projects establish the landscape unit value of each tree to be removed. The method involves assessment of species, condition, location and heritage status. HortScience has provided these assessments in a number of residential and commercial development projects, assisting the development team is establishing replanting requirements.
City of Oakland, CA
HortScience worked with the City's environmental consultant to assess over 250 trees proposed for removal as part of the Lake Merritt improvement projects.  In addition to evaluating tree health and structural condition, we established the value of each tree using the standard methods. We also used the iEco module of the iTree software to asses economic and environmental benefits of trees proposed for removal and those proposed for planting.
Farmers Insurance Group. Pleasanton, CA

HortScience established the value of 25 trees removed from a private property in San Rafael CA using the standard methods for landscape trees.


<return to top>


Plant Problem Diagnosis


Hort Tech Landscape Management. Palm Desert, CA


HortScience was asked to diagnose the cause of pine tree decline and death throughout the golf course at The Vintage Club. We evaluated site conditions, collected samples, and performed laboratory analuses to identify the cause and recommended treatments.
East Bay Regional Parks District. Oakland, CA
Arendwood Historic Farm in Fremont, CA was planted with sugar gum trees in the late 1800's. The historic trees were declining and falling. HortScience was asked to identify the cause of the decline. We examoned the soild profile to depths of 5', collected soil and roots samples, performed laboratory tests, and inspected trees that had failed. We identified a root disease organism that was unusually virulent because the trees were stressed by the saline subsoil.
Dolce Hayes Mansion, San Jose CA
HortScience was asked to diagnose the cause of a crown failure in a Canary Island date palm and evaluate the current health of other date palms. We examined a cross-section of the pineapple and photographs, and determined the most likely cause of the failure. We evaluated the condition of other palms and provided recommendations for their management.
Gateway Landscape Construction, Inc. Livermore, CA
HortScience was asked to diagnose the cause of a death of a Canary Island date palm at the Union Landing Shopping Center. We evaluated site conditions and cultural practices to determine the cause of death. We also prepared transplanting specifications to replace the dead palm.

<return to top>


Bartlett Tree Experts

HortScience is now a division of Bartlett Tree Experts. We are supported by the Bartlett Tree Research Laboratories and its team of scientists and technicians, which is a significant resource that enables us to enhance our consulting services. Bartlett is also a world-class tree care company that has been in business for over one hundred years. HortScience | Bartlett Consulting will operate independently, but if you have need of tree care, local Bartlett offices are available to provide a full range of tree care services, including pruning and pest management.

© 2024 HortScience | Bartlett Consulting. All rights reserved.  |  Privacy Policy  |  Site Map  |  Contact Us

Find us on Facebook  Find us on Facebook