Calculator Inputs
Example Data Table
Sample inputs and typical output for a medium landscape zone.
| Gross Area | Unplantable % | Layout | Spacing | Contingency % | Total Trees (approx.) |
|---|---|---|---|---|---|
| 2,500 m² | 10% | Rectangular | 3 m × 3 m | 5% | ~92 |
| 2,500 m² | 10% | Staggered | 3 m × 3 m | 5% | ~106 |
Formula Used
The calculator converts all areas to square meters and applies exclusions: Net Area = Gross Area × (1 − Unplantable%/100).
- Spacing-based: Area per Tree = Row Spacing × Tree Spacing × Layout Factor
- Rectangular factor: 1.000
- Staggered factor: 0.866 (triangular packing approximation)
- Base Count: Net Area ÷ Area per Tree
- Density-based: Base Count = (Net Area/10,000) × Trees per Hectare
- Contingency: Contingency Trees = ceil(Rounded Base × Contingency%/100)
- Total Trees: Total = Rounded Base + Contingency Trees
How to Use This Calculator
- Choose Spacing-based if you know spacing distances; otherwise select Density-based.
- Enter the gross planting area and select the correct unit.
- Set unplantable percent to exclude paths, pits, and fixed obstructions.
- Pick the layout (rectangular or staggered) to reflect field installation.
- Add a contingency percent to meet survival or replacement requirements.
- Optionally enter plot length and width to cross-check row totals.
- Optionally add a species mix to split procurement quantities.
- Click Calculate, then export results using CSV or PDF.
Professional Article
1) Planning context for construction sites
Tree counts affect budgets, logistics, and compliance on many projects. Landscape plans often require minimum canopy coverage, screening, or compensatory planting for removed vegetation. This calculator translates site area and planting rules into an actionable quantity for procurement and installation scheduling.
For estimating, treat each planting zone separately, especially when soil depths vary. Temporary works, haul routes, and crane pads often reduce available space. Document assumptions early, then update counts after grading, utilities, and pavement lines are finalized. This supports accurate orders and minimizes rework later.
2) Area, exclusions, and net plantable zone
Start with gross planting area, then exclude hardscape, utility corridors, access paths, and safety buffers. Typical unplantable allowances range from 10% to 25% depending on site congestion. Net area is used for all quantities, making the output consistent with real buildable green space.
3) Spacing method with practical benchmarks
Spacing-based planning is common when drawings specify tree-to-tree distances. For example, 3 m × 3 m rectangular spacing yields about 1,111 trees per hectare before exclusions. Wider spacing reduces maintenance and irrigation demand, while tighter spacing increases early canopy closure but raises competition and pruning needs.
4) Layout choice and staggered efficiency
A staggered (triangular) layout can increase capacity in the same net area. Using the same 3 m × 3 m spacings, staggered packing increases density by roughly 15% (about 1,283 trees per hectare). Use staggered patterns only where staking, sightlines, and equipment access remain workable.
5) Contingency, species split, and reporting
Construction planting programs typically include 5% to 15% contingency to cover damage, replacement, or survival targets. The optional species mix converts totals into purchase lines, supporting nursery lead times and phased deliveries. Export the CSV or PDF report to share assumptions, quantities, and calculated densities with stakeholders.
FAQs
1) Should I use spacing-based or density-based?
Use spacing-based when drawings specify row and tree spacing. Use density-based when a guideline specifies trees per hectare or per acre. Both methods apply exclusions and contingency consistently.
2) What does unplantable percent include?
Include pavements, paths, ramps, utility easements, drainage features, retaining structures, and safety buffers. If your plan has multiple planting zones, run the calculator per zone for better accuracy.
3) Why does staggered layout increase the count?
Staggered rows reduce unused gaps between trees, improving packing efficiency. The calculator uses a standard triangular packing factor, which typically yields about 15% more trees for the same spacing inputs.
4) How do I choose contingency percentage?
Start with 5% for controlled sites and raise to 10–15% for harsh conditions, heavy traffic, or strict survival clauses. Align the value with contract specifications and local replacement obligations.
5) What is the purpose of the length and width fields?
They provide a quick row-based cross-check when spacing is used. The estimate assumes straight rows and ignores edge setbacks, so treat it as validation rather than a final count.
6) Can I use this for street medians or linear corridors?
Yes. Enter the corridor planting area and apply a higher unplantable percentage for driveways, poles, and sight triangles. For long corridors, consider running separate sections where spacing or constraints change.
7) Does the species mix need to total 100%?
No. If you enter positive values, the calculator normalizes them to 100% automatically and allocates counts accordingly. This helps when you only know approximate ratios during early design and estimating.