Woody Plant Appraisal Data Collection for Shrubs, Trees and Vines

Summary: Plant appraisal data collection acts as accurately and precisely as equipment and experience in tree condition, identification, placement and size allow.

Plant appraisers need to know what they are looking at and for during plant appraisal data collection, especially when they will have to adjust the way of measuring tree height and trunk diameter and height for deformed, gall-riddled, low-branching, sloping, swollen, wounded trees; illustration of rot column moving up from a basal wound: Paul A. Mistretta, USDA Forest Service, Bugwood.org, CC BY 3.0 United States, via Forestry Images

The article Plant Appraisal Data Collection (Part One) appearing in the April 2019 issue of Arborist News and authored by The Council of Tree & Landscape Appraisers advises of more to come.

Plant appraisal data collection brings together tree diameter-, height-, number-based quantitative counts, measurements, rankings and ratings through off- and on-site research of landscape and tree features. It communicates accuracy close to true value and precision close to average value even as it conveys imprecision from random errors and inaccuracy from systematic errors. It dispenses inexactness in short, simple on-site rounding of pi (π), tree heights and trunk diameters to 3.14, the nearest foot and the nearest one-tenth inch.

Plant appraisal data collection entails rounding minimum numbers of digits, two or three in total cost and value estimates, for unbiased results without unduly compromised accuracy.

Greater numbers of significant figures, with $75,649 rounded to $80,000, $76,000 or $75,600, furnishes greater implied precision of plus or minus 12, 1 and 0.1 percent.

Mathematic impacts generate appropriate numbers, as in reliability of estimate at two significant digits guiding cost conclusions, where depreciation gives diminished precision to the overall process. Julian Dunster of Dunster & Associates Environmental Consultants in Victoria, British Columbia, Canada, handles plant appraisal data collection as honing what to look at and for. Site information including address, climate, hardiness zone, soil, structures, topography and use from documents, drawings, laws, maps, photographs, plans and surveys initiates plant appraisal data collection.

Plant appraisal data collection judges as negative, neutral or positive plant interactions with such infrastructure as bridges, pavement, power and water systems, roads, sculptures and walls.

Plant appraisal data collection knits condition, identification, placement and size, with palm tree and trunk heights from grade to last-expanded frond and to spear leaf base.

Plant appraisal data collection logs 6- and 12-inch (15- and 30-centimeter) above-grade heights for nursery trunk diameters respectively through and greater than 4 inches (10 centimeters). It measures trunk diameters at 4.5-foot (1.4-meter) and at 1.3- to 1.5-meter (4.3- and 4.9-foot) above-grade heights respectively outside U.S. nurseries and outside the United States. Best-size, field-adjusted representations necessitate high-side and smallest-diameter measurements near 4.5-foot above-grade heights for leaning and vertical slope-planted trunks and for deformed, gall-riddled, low-branching, swollen, wounded trees.

Plant appraisal data collection offers best-size, field-adjusted measurements at 4.5-foot above-grade heights for trunks multi-stemming near ground level and on the perpendicular for flat-grounded, leaning trunks.

Best-size, field-adjusted measurements of trunks multi-stemmed below or above 4.5-foot above-grade heights pinpoint respective 3.5-foot (1.07-meter) heights above the fork bottom and at 4.5-foot above-grade heights.

Basal swelling and excessive trunk flare queue up 4.5-plus-foot above-grade heights or qualify with inaccessible and removed trees for substitute measurements of same-size, same-species area trees. Plant appraisal data collection relies upon calipers and, despite overestimates for other than near-perfect circular trunks and for easy use, tapes for tree trunk diameter estimates. Calipers supply quadratic mean diameters (QMD) from square roots of products of two right-angle diameter measurements, for cross-sectional area estimates even of asymmetric and elliptical trunks.

Plant appraisal data collection tallies cross-sectional areas from trunk circumferences or diameters and teams cross-sectional areas tending away from circular shapes with smaller true circumference areas.

Wounded trees require a different way of measuring their diameters and heights and, in their most damaged conditions, suggest substitute measurements of same-size, same-species area trees; illustration of wounds, cause of decay and defect, with depictions of poorly healed stem stub, poorly healed branch stub, mechanical wound and old fire wound: Paul A. Mistretta, USDA Forest Service, 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:

Plant appraisers need to know what they are looking at and for during plant appraisal data collection, especially when they will have to adjust the way of measuring tree height and trunk diameter and height for deformed, gall-riddled, low-branching, sloping, swollen, wounded trees; illustration of rot column moving up from a basal wound; illustration of rot column moving up from a basal wound: Paul A. Mistretta, USDA Forest Service, Bugwood.org, CC BY 3.0 United States, via Forestry Images @ https://www.forestryimages.org/browse/detail.cfm?imgnum=1505078

Wounded trees require a different way of measuring their diameters and heights and, in their most damaged conditions, suggest substitute measurements of same-size, same-species area trees; illustration of wounds, cause of decay and defect, with depictions of poorly healed stem stub, poorly healed branch stub, mechanical wound and old fire wound: Paul A. Mistretta, USDA Forest Service, Bugwood.org, CC BY 3.0 United States, via Forestry Images @ https://www.forestryimages.org/browse/detail.cfm?imgnum=1505081

For further information:

The Council of Tree & Landscape Appraisers. April 2019. "Plant Appraisal Data Collection (Part One)." Arborist News 28(2): 14-21.

Dunster, J. 2014. Documenting Evidence: Practical Guidance for Arborists. Dunster & Associates Environmental Consultants Ltd. Victoria, BC, Canada: First Choice Books.

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Available @ https://earth-and-space-news.blogspot.com/2019/02/plant-appraisal-estimate-scope-data.html

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Available @ https://earth-and-space-news.blogspot.com/2016/08/changing-places-tree-nutrient-movement.html

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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

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Available @ https://earth-and-space-news.blogspot.com/2016/02/bark-protective-survival-mechanisms.html

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Available @ https://earth-and-space-news.blogspot.com/2016/01/lita-model-linear-index-of-tree.html

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Available @ https://earth-and-space-news.blogspot.com/2015/12/tree-lightning-protection-systems-site.html

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Available @ https://earth-and-space-news.blogspot.com/2015/10/tree-lightning-protection-systems.html

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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

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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

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Available @ https://earth-and-space-news.blogspot.com/2014/08/flood-tolerant-trees-in-worst-case.html

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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