Cost Approach Approximates Plant Repair, Replacement or Restoration

Summary: An article in Arborist News August 2019 applies the cost approach to appraising repairing, replacing or restoring plant usefulness.

The cost approach gives dead trees a rating of zero percent for maximum landscape benefit and feature uselessness and maximum physical deterioration even though research by Merlin K.-F. Bader and Sebastian Leuzinger indicates continued interactions of stump roots with the soil food web; beech tree (Fagus spp.), Baker's Hill, Mickleton, Gloucestershire, South West England; Saturday, Feb. 2, 2008: Philip Halling, CC BY SA 2.0 Generic, via Wikimedia Commons

The article The Cost Approach: Methods, Techniques, and Depreciation by The Council of Tree & Landscape Appraisers in Arborist News August 2019 alludes to plant appraisal for repaired, replaced or restored usefulness.

The cost approach broaches direct costs as actual or estimated equipment, labor, material and supply costs and extrapolated costs as largest commonly available nursery-grown tree costs. Three cost approach methods consider repair costs for correcting damages and controlling coming losses; replacement costs for restoring benefits; and reproduction costs for choosing exact replicas. Damage and destruction appraisals, preconstruction bonding, some insurance claims and tree inventories demand the reproduction cost method duplicating landscape features more than functional replacement restoring benefits.

Direct cost (DCT) and extrapolated trunk formula (TFT) and cost compounding (CCT) techniques respectively express direct damage-related treatments and large-plant costs from proportionally expanded nursery-plant costs.

Common landscape applications feature extrapolated basic costs from figuring largest commonly available nursery plants even as seedling prices furnish forestry or woodland settings extrapolated basic costs.

Nursery plant costs give the figures that nursery price schedules generate for landscape professionals, with delivery, planting, site clean-up and staked-period maintenance grouped as additional costs. TFT extrapolations have large-plant costs directly proportional to nursery-plant unit cost per square inch (square centimeter) of trunk cross-sectional area, commonly at 4.5 feet (1.37 meters). They involve foot (meter) of clear-trunk or total palm height, square foot (square meter) of shrub canopy or cubic foot (cubic meter) of shrub crown volume.

The extrapolated cost approach judges same-species, same-size, same-cultivar appraised and nursery trees for reproduction costs and, sometimes functional replacement costs, different-sized, different-species appraised and nursery trees.

The CCT formula keys CC = PC x (1 + i)ⁿ as present cost; defensible, property-specific, reasonable interest rate; and years to benefit or size parity.

Depreciation, as suboptimum external, functional and physical factors expressed monetarily, looks at appraised versus ideal, new items, with the former of ill-featured, ill-placed, ill-sited, lesser quality. Form, health and structural integrity make up the depreciation factor of physical deterioration, with ideal living conditions at 100 percent and dead condition of 0 percent. Plant genetics, placement and superadequacy through excess density or size and site soil and water number among functional limitations beyond cure or necessitating costly, repeated treatments.

The cost approach observes external limitations, outside owner control and property, of climate-zone changes; easements, laws and ordinances; irrigation restrictions; serious area pests; and water-use limitations.

Owners of easements that prohibit area tree heights possess legal rights to pruning, removing or topping private-property trees and provoke depreciation ratings below limitation-free 100 percent.

Additional costs that quantify clean-up, installation and maintenance as far as practically and reasonably necessary into the future sometimes queue up beyond basic and depreciated costs. Recovery sometimes requires additional costs as pruning, root and soil treatments relating directly to damage, respecting best practices and industry standards, and resisting excessive, uncommon recourses. The effective date of the valuation structures estimated additional costs, just as it structures basic direct costs, basic extrapolated CCT and TFT costs and depreciated costs.

The cost approach tallies basic costs, with or without additional and depreciated costs, through direct or extrapolated cost techniques and repair, replacement or reproduction cost methods.

The cost approach opposes "excessive" and "uncommon" treatments even though such prescriptions would sustain, and thank, this street tree for reducing light and noise pollution; releasing exudates and oxygen; removing atmospheric carbon dioxide, heavy metals and pollutant particles; and rendering built environments beautiful, healthy and nature-, people- and place-friendly; Dr. Whitney Cranshaw (1986) inspects poor tree placement: William Jacobi, Colorado State University, Bugwood.org, CC BY 3.0 United States, via Forestry Images

Acknowledgment

My special thanks to talented artists and photographers/concerned organizations who make their fine images available on the internet.

Image credits:

The cost approach gives dead trees a rating of zero percent for maximum landscape benefit and feature uselessness and maximum physical deterioration even though research by Merlin K.-F. Bader and Sebastian Leuzinger indicates continued interactions of stump roots with the soil food web; beech tree (Fagus spp.), Baker's Hill, Mickleton, Gloucestershire, South West England; Saturday, Feb. 2, 2008: Philip Halling, CC BY SA 2.0 Generic, via Wikimedia Commons @ https://commons.wikimedia.org/wiki/File:Tree_stump,_Brake's_Hill_-_geograph.org.uk_-_681524.jpg;
Philip Halling, CC BY SA 2.0 Generic, via Geograph Britain and Ireland @ https://www.geograph.org.uk/photo/681524

The cost approach opposes "excessive" and "uncommon" treatments even though such prescriptions would sustain, and thank, this street tree for reducing light and noise pollution; releasing exudates and oxygen; removing atmospheric carbon dioxide, heavy metals and pollutant particles; and rendering built environments beautiful, healthy and nature-, people- and place-friendly; Dr. Whitney Cranshaw (1986) inspects poor tree placement: William Jacobi, Colorado State University, Bugwood.org, CC BY 3.0 United States, via Forestry Images @ https://www.forestryimages.org/browse/detail.cfm?imgnum=5356999

For further information:

Bader, M.K.-F.; and S. Leuzinger. 25 July 2019. "Hydraulic Coupling of a Leafless Kauri Tree Remnant to Conspecific Hosts." iScience. DOI: https://doi.org/10.1016/j.isci.2019.05.009.
Available @ https://www.cell.com/iscience/fulltext/S2589-0042(19)30146-4?_returnURL=https%3A%2F%2Flinkinghub.elsevier.com%2Fretrieve%2Fpii%2FS2589004219301464%3Fshowall%3Dtrue

Cell Press. 25 July 2019. "A Tree Stump That Should Be Dead Is Still Alive; Here's Why." Phys.Org > Earth > Environment.
Available @ https://phys.org/news/2019-07-tree-stump-dead-alive.html

The Council of Tree & Landscape Appraisers. August 2019. "The Cost Approach: Methods, Techniques, and Depreciation." Arborist News 28(4): 12-21.

Gilman, Ed. 2011. An Illustrated Guide to Pruning. Third Edition. Boston MA: Cengage.

Hayes, Ed. 2001. Evaluating Tree Defects. Revised, Special Edition. Rochester MN: Safe Trees.

Klein, JoAnna. 25 July 2019. "Tree Stumps Are Dead, Right? This One Was Alive." The New York Times > Science > Trilobites.
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Marriner, Derdriu. 28 July 2019. "Indirect Watering Devices Are There for Newly Transplanted Urban Trees." Earth and Space News. Sunday.
Available @ https://earth-and-space-news.blogspot.com/2019/07/indirect-watering-devices-are-there-for.html

Marriner, Derdriu. 30 June 2019. "Plant Appraisal Data Collection Allies Off-Site and On-Site Research." Earth and Space News. Sunday.
Available @ https://earth-and-space-news.blogspot.com/2019/06/plant-appraisal-data-collection-allies.html

Marriner, Derdriu. 26 May 2019. "Wire Basket Removal or Wire Basket Retention: Girdling or Stable Roots." Earth and Space News. Sunday.
Available @ https://earth-and-space-news.blogspot.com/2019/05/wire-basket-removal-or-wire-basket.html

Marriner, Derdriu. 28 April 2019. "Woody Plant Appraisal Data Collection for Shrubs, Trees and Vines." Earth and Space News. Sunday.
Available @ https://earth-and-space-news.blogspot.com/2019/04/woody-plant-appraisal-data-collection.html

Marriner, Derdriu. 30 March 2019. "Balancing Roadside Tree Benefits and Risk of Streetscape Tree Crashes." Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2019/03/balancing-roadside-tree-benefits-and.html

Marriner, Derdriu. 17 February 2019. “Plant Appraisal Estimate, Scope, Data, Analysis, Reconciliation, Report.” Earth and Space News. Sunday.
Available @ https://earth-and-space-news.blogspot.com/2019/02/plant-appraisal-estimate-scope-data.html

Marriner, Derdriu. 27 January 2019. “Urban Tree Vulnerability in Residential Toronto, Ontario, Canada.” Earth and Space News. Sunday.
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Marriner, Derdriu. 30 December 2018. "Plant Appraisal: Cost and Value Estimates and Economic Principles." Earth and Space News. Sunday.
Available @ https://earth-and-space-news.blogspot.com/2018/12/plant-appraisal-cost-and-value.html

Marriner, Derdriu. 23 December 2018. "Six-Year Forest Health Ambassador Program of Oakville, Ontario, Canada." Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2018/12/six-year-forest-health-ambassador.html

Marriner, Derdriu. 21 October 2018. "Nursery Production Systems: Tough Urban Landscape Trees on Rough Sites." Earth and Space News. Sunday.
Available @ https://earth-and-space-news.blogspot.com/2018/10/nursery-production-systems-tough-urban.html

Marriner, Derdriu. 16 September 2018. "Induced-Resistance Agents, Silicon Fertilizers, Synthetic Fungicides." Earth and Space News. Sunday.
Available @ https://earth-and-space-news.blogspot.com/2018/09/induced-resistance-agents-silicon.html

Marriner, Derdriu. 26 August 2018. "Nursery Production Systems for Successful Urban Tree Plantings." Earth and Space News. Sunday.
Available @ https://earth-and-space-news.blogspot.com/2018/08/nursery-production-systems-for.html

Marriner, Derdriu. 29 July 2018. "Tree Roots Branch in Fabric Containers But Circle and Girdle Plastic." Earth and Space News. Sunday.
Available @ https://earth-and-space-news.blogspot.com/2018/07/tree-roots-branch-in-fabric-containers.html

Marriner, Derdriu. 30 June 2018. "Wood Decay Fungi Management of Terminal Urban Pathogens." Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2018/06/wood-decay-fungi-management-of-terminal.html

Marriner, Derdriu. 27 May 2018. "Downtown Commercial Streetscape Tree Populations in Toronto, Canada." Earth and Space News. Sunday.
Available @ https://earth-and-space-news.blogspot.com/2018/05/downtown-commercial-streetscape-tree.html

Marriner, Derdriu. 28 April 2018. “Mushroom-Forming and Non-Mushroom-Forming Fungal Life Cycle Traits.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2018/04/mushroom-forming-and-non-mushroom.html

Marriner, Derdriu. 17 March 2018. “Emerald Ash Borer Rapid Response Community Preparedness Project.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2018/03/emerald-ash-borer-rapid-response.html

Marriner, Derdriu. 17 February 2018. “Tree Retention by Arborists for Wildlife Habitat Friendly Tree Care.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2018/02/tree-retention-by-arborists-for.html

Marriner, Derdriu. 14 January 2018. “Integrated Vegetation Management Study in North and South Yukon, Canada.” Earth and Space News. Sunday.
Available @ https://earth-and-space-news.blogspot.com/2018/01/integrated-vegetation-management-study.html

Marriner, Derdriu. 9 December 2017. “Tree Inventories: Preemptive and Proactive or Piecemeal and Reactive.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2017/12/tree-inventories-preemptive-and.html

Marriner, Derdriu. 25 November 2017. “Chlorantraniliprole Reduced-Risk Insecticides Get Leaf-Eaters Not Bees.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2017/11/chlorantraniliprole-reduced-risk.html

Marriner, Derdriu. 28 October 2017. “Palm Plant Health Care: Abiotic, Biotic Stress Culture and Management.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2017/10/palm-plant-health-care-abiotic-biotic.html

Marriner, Derdriu. 16 September 2017. “Predawn Leaf Water Potentials Indicate Crown Dieback and Water Status.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2017/09/predawn-leaf-water-potentials-indicate.html

Marriner, Derdriu. 19 August 2017. “Palm Tree Identification and Pruning of Native and Naturalizable Palms.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2017/08/palm-tree-identification-and-pruning-of.html

Marriner, Derdriu. 22 July 2017. “Commonly Planted, Potentially Phytoremediating Street Tree Species.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2017/07/commonly-planted-potentially.html

Marriner, Derdriu. 17 June 2017. “Root Loss From Root Pruning and Root Shaving of Stem-Girdling Roots.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2017/06/root-loss-from-root-pruning-and-root.html

Marriner, Derdriu. 27 May 2017. “Age and Canopy Area Cost Less and Tell More in Urban Tree Inventories.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2017/05/age-and-canopy-area-cost-less-and-tell.html

Marriner, Derdriu. 22 April 2017. “Urban Root Management: Big Infrastructure, Small Space, Stressed Roots.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2017/04/urban-root-management-big.html

Marriner, Derdriu. 12 March 2017. “Flexural Elasticity Modulus: Trees and Watersprouts Bend or Break.” Earth and Space News. Sunday.
Available @ https://earth-and-space-news.blogspot.com/2017/03/flexural-elasticity-modulus-trees-and.html

Marriner, Derdriu. 18 February 2017. “Plant Health Care Diagnostics When Plants and Places Wrong One Another.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2017/02/plant-health-care-diagnostics-when.html

Marriner, Derdriu. 14 January 2017. “Tree Fertilization for Fine Root Growth and Whole Root System Effects.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2017/01/tree-fertilization-for-fine-root-growth.html

Marriner, Derdriu. 17 December 2016. “Abiotic and Biotic Stress in Low Maintenance Tree Health Care Programs.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2016/12/abiotic-and-biotic-stress-in-low.html

Marriner, Derdriu. 19 November 2016. “Organic Amendments to Compacted Degraded Urban Highway Roadsides.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2016/11/organic-amendments-to-compacted.html

Marriner, Derdriu. 15 October 2016. “Tree Protection Zones by Arborists for All Construction Project Phases.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2016/10/tree-protection-zones-by-arborists-for.html

Marriner, Derdriu. 17 September 2016. “Stormwater Runoff Landscaping With Urban Canopy Cover and Groundcover.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2016/09/stormwater-runoff-landscaping-with.html

Marriner, Derdriu. 13 August 2016. “Changing Places: Tree Nutrient Movement Down, Tree Water Movement Up.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2016/08/changing-places-tree-nutrient-movement.html

Marriner, Derdriu. 16 July 2016. “Treated or Untreated Oriental Bittersweet Vine Management Cut-Stumping.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2016/07/treated-or-untreated-oriental.html

Marriner, Derdriu. 18 June 2016. “Tree Injection Site Procedures: Manufacturer's Instructions and Labels.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2016/06/tree-injection-site-procedures.html

Marriner, Derdriu. 22 May 2016. “Electrical Utility Area Temperate Urban Street Trees: Pruned Regrowth.” Earth and Space News. Sunday.
Available @ https://earth-and-space-news.blogspot.com/2016/05/electrical-utility-area-temperate-urban.html

Marriner, Derdriu. 16 April 2016. “Tree Injection Methods: Treatment Option in Integrated Pest Management.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2016/04/tree-injection-methods-treatment-option.html

Marriner, Derdriu. 6 March 2016. “Bare-Rooted Ornamental Urban Transplants: Amendments Against Mortality.” Earth and Space News. Sunday.
Available @ https://earth-and-space-news.blogspot.com/2016/03/bare-rooted-ornamental-urban.html

Marriner, Derdriu. 28 February 2016. “Bark Protective Survival Mechanisms Foil Deprivation, Injury, Invasion.” Earth and Space News. Sunday.
Available @ https://earth-and-space-news.blogspot.com/2016/02/bark-protective-survival-mechanisms.html

Marriner, Derdriu. 23 January 2016. "LITA Model: Linear Index of Tree Appraisal of Large Urban Swedish Trees." Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2016/01/lita-model-linear-index-of-tree.html

Marriner, Derdriu. 19 December 2015. “Tree Lightning Protection Systems: Site, Soil, Species True Designs.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2015/12/tree-lightning-protection-systems-site.html

Marriner, Derdriu. 24 October 2015. “Tree Lightning Protection Systems Tailored to Sites, Soils, Species.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2015/10/tree-lightning-protection-systems.html

Marriner, Derdriu. 15 August 2015. “Tree Friendly Urban Soil Management: Amend, Fertilize, Mulch, Till!” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2015/08/tree-friendly-urban-soil-management.html

Marriner, Derdriu. 13 June 2015. “Tree Friendly Urban Soil Management: Assemble, Assess, Assist, Astound.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2015/06/tree-friendly-urban-soil-management.html

Marriner, Derdriu. 18 April 2015. “Tree Wound Responses: Healthy Wound Closures by Callus and Woundwood.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2015/04/tree-wound-responses-healthy-wound.html

Marriner, Derdriu. 15 February 2015. “Urban Forest Maintenance and Non-Maintenance Costs and Benefits.” Earth and Space News. Sunday.
Available @ https://earth-and-space-news.blogspot.com/2015/02/urban-forest-maintenance-and-non.html

Marriner, Derdriu. 13 December 2014. “Tree Dwelling Symbionts: Dodder, Lichen, Mistletoe, Moss and Woe-Vine.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2014/12/tree-dwelling-symbionts-dodder-lichen.html

Marriner, Derdriu. 18 October 2014. “Tree Cable Installation Systems Lessen Target Impact From Tree Failure.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2014/10/tree-cable-installation-systems-lessen.html

Marriner, Derdriu. 16 August 2014. “Flood Tolerant Trees in Worst-Case Floodplain and Urbanized Scenarios.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2014/08/flood-tolerant-trees-in-worst-case.html

Marriner, Derdriu. 14 June 2014. “Integrated Vegetation Management of Plants in Utility Rights-of-Way.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2014/06/integrated-vegetation-management-of.html

Marriner, Derdriu. 12 April 2014. “Tree Twig Identification: Buds, Bundle Scars, Leaf Drops, Leaf Scars.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2014/04/tree-twig-identification-buds-bundle.html

Marriner, Derdriu. 15 February 2014. “Tree Twig Anatomy: Ecosystem Stress, Growth Rates, Winter Identification.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2014/02/tree-twig-anatomy-ecosystem-stress.html

Marriner, Derdriu. 14 December 2013. “Community and Tree Safety Awareness During Line- and Road-Clearances.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2013/12/community-and-tree-safety-awareness.html

Marriner, Derdriu. 13 October 2013. “Chain-Saw Gear and Tree Work Related Personal Protective Equipment.” Earth and Space News. Sunday.
Available @ https://earth-and-space-news.blogspot.com/2013/10/chain-saw-gear-and-tree-work-related.html

Marriner, Derdriu. 12 October 2013. “Storm Damaged Tree Clearances: Matched Teamwork of People to Equipment.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2013/10/storm-damaged-tree-clearances-matched.html

Marriner, Derdriu. 17 August 2013. “Storm Induced Tree Damage Assessments: Pre-Storm Planned Preparedness.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2013/08/storm-induced-tree-damage-assessments.html

Marriner, Derdriu. 15 June 2013. “Storm Induced Tree Failures From Heavy Tree Weights and Weather Loads.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2013/06/storm-induced-tree-failures-from-heavy.html

Marriner, Derdriu. 13 April 2013. “Urban Tree Root Management Concerns: Defects, Digs, Dirt, Disturbance.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2013/04/urban-tree-root-management-concerns.html

Marriner, Derdriu. 16 February 2013. “Tree Friendly Beneficial Soil Microbes: Inoculations and Occurrences.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2013/02/tree-friendly-beneficial-soil-microbes.html

Marriner, Derdriu. 15 December 2012. “Healthy Urban Tree Root Crown Balances: Soil Properties, Soil Volumes.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2012/12/healthy-urban-tree-root-crown-balances.html

Marriner, Derdriu. 13 October 2012. “Tree Adaptive Growth: Tree Risk Assessment of Tree Failure, Tree Strength.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2012/10/tree-adaptive-growth-tree-risk.html

Marriner, Derdriu. 11 August 2012. “Tree Risk Assessment Mitigation Reports: Tree Removal, Tree Retention?” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2012/08/tree-risk-assessment-mitigation-reports.html

Marriner, Derdriu. 16 June 2012. “Internally Stressed, Response Growing, Wind Loaded Tree Strength.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2012/06/internally-stressed-response-growing.html

Marriner, Derdriu. 14 April 2012. “Three Tree Risk Assessment Levels: Limited Visual, Basic and Advanced.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2012/04/three-tree-risk-assessment-levels.html

Marriner, Derdriu. 19 February 2012. “Qualitative Tree Risk Assessment: Risk Ratings for Targets and Trees.” Earth and Space News. Sunday.
Available @ https://earth-and-space-news.blogspot.com/2012/02/qualitative-tree-risk-assessment-risk.html

Marriner, Derdriu. 18 February 2012. “Qualitative Tree Risk Assessment: Falling Trees Impacting Targets.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2012/02/qualitative-tree-risk-assessment.html

Marriner, Derdriu. 10 December 2011. “Tree Risk Assessment: Tree Failures From Defects and From Wind Loads.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2011/12/tree-risk-assessment-tree-failures-from.html

Marriner, Derdriu. 15 October 2011. “Five Tree Felling Plan Steps for Successful Removals and Worker Safety.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2011/10/five-tree-felling-plan-steps-for.html

Marriner, Derdriu. 13 August 2011. “Natives and Non-Natives as Successfully Urbanized Plant Species.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2011/08/natives-and-non-natives-as-successfully.html

Marriner, Derdriu. 11 June 2011. “Tree Ring Patterns for Ecosystem Ages, Dates, Health and Stress.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2011/06/tree-ring-patterns-for-ecosystem-ages.html

Marriner, Derdriu. 9 April 2011. “Benignly Ugly Tree Disorders: Oak Galls, Powdery Mildew, Sooty Mold, Tar Spot.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2011/04/benignly-ugly-tree-disorders-oak-galls.html

Marriner, Derdriu. 12 February 2011. “Tree Load Can Turn Tree Health Into Tree Failure or Tree Fatigue.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2011/02/tree-load-can-turn-tree-health-into.html

Marriner, Derdriu. 22 December 2010. “Tree Electrical Safety Knowledge, Precautions, Risks and Standards.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2010/12/tree-electrical-safety-knowledge.html

Scully, Ruby Prosser. 25 July 2019. "Tree Stumps That Should Be Dead Can Be Kept Alive by Nearby Trees." NewScientist > Environment.
Available @ https://www.newscientist.com/article/2211209-tree-stumps-that-should-be-dead-can-be-kept-alive-by-nearby-trees/