Eighteen High-Risk Trees and a $42,000 Budget
Lakeside manages 6,800 park and street trees. A Level 2 risk assessment of 420 trees in 12 high-use parks identified 18 trees rated high risk. Removal of all 18 is bid at $61,000; the tree budget has $42,000 available before the fiscal year ends in four months. One tree is a 28-inch silver maple with a large dead limb directly over the only accessible entrance to a playground and over a sidewalk on a school route. Another is a 22-inch cottonwood with a 40% lean toward a picnic shelter used by a summer camp. Ten of the trees are in a low-use natural area along a service road. The parks director wants a ranked list and a defensible explanation for anything left standing.
1. Build a prioritization method for the 18 trees and allocate the $42,000.
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Rank by risk, not by removal cost: risk is the likelihood of failure multiplied by the consequences, weighted by how often people are actually under the tree.
- Silver maple (playground and school route): the dead limb is the immediate problem. Pruning it off is likely $1,000–$3,000 and removes most of the exposure today. Removing the whole tree may not be necessary this year. Do the prune now, then reassess.
- Cottonwood (lean toward an occupied shelter): high occupancy during camp season and a lean that is hard to mitigate short of removal or major reduction. Fund removal or reduction, about $6,000–$10,000, and close the shelter until it is done.
- Remaining six high-use park trees: treat individually - prune, cable, or remove depending on defect. Budget roughly $15,000–$20,000.
- Ten natural-area trees: low occupancy, service road only. Restrict access with temporary fencing or gate closure, set a re-inspection date, and schedule removals into next fiscal year's capital request.
Use the mitigation hierarchy before removal: prune, reduce, support, move the target, restrict access. Only then remove. Document each decision with the assessment method and date so the ranking is auditable.
2. What is your obligation and liability exposure for the high-risk trees you cannot fund this year?
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Documenting a tree does not discharge the duty; acting reasonably does. The defensible position is that you identified the risk, reduced it as far as resources allowed, and have a plan.
For each unfunded tree:
- Record the assessment level, method, date, and defect, in a system a successor can use.
- Apply interim measures: close the service road or fence the area, post notice, reroute the path, remove the target, or do a crown reduction if it materially lowers risk.
- Set a re-inspection interval - shorter for the higher-consequence trees - and actually keep it.
- Send a written memo to the risk manager and council stating the unfunded list, the residual risk, and the request, before an incident occurs.
Liability exposure varies by jurisdiction, and immunity doctrines are unreliable for operational decisions like failing to act on a known defect. The practical exposure is a documented known hazard with no action and no interim control.
3. How would you restructure the program so this backlog does not recur?
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The backlog is a symptom of reactive, project-by-project spending. Convert it to a cycle.
- Inventory and risk ratings in GIS for all 6,800 trees, with assessment levels and inspection dates.
- Cycle: a five-year inspection cycle citywide and a one- to two-year cycle for trees over high-use targets, with a written standard for what triggers an elevated assessment.
- Budget line: a recurring amount based on cost per tree per year - often $8–$12 for a mixed urban forest - rather than an annual scramble.
- Workforce: in-house crew for routine pruning and small removals, an on-call contract for large or technical removals, and training so more staff can do Level 1 and 2 assessments.
- Planting for the future: species and size diversity, and avoid placing large, brittle-wooded trees directly over playgrounds, shelters, and school routes where the next generation inherits the conflict.
Track cost per tree and the number of high-risk trees closed each year; that is the metric that demonstrates the program is working.