Forestry Tools Forestry Seedling Count & Spacing Calculator

Forestry Seedling Count & Spacing Calculator

Enter area, target stems per area, survival rate, and supplement rate to calculate the seedlings you need.

A pure count calculator for planting plans, reforestation work, and planting renewal. It stays focused on numbers, so it works well across regions.

Area × density Survival / supplement Global-ready
How to use

How to use

  1. • Enter the plantable area and choose the unit.
  2. • Enter the target stems per hectare or acre, and choose the matching unit.
  3. • Enter the expected survival rate and any supplement rate for replacements.
  4. • Review the required seedlings and square-equivalent spacing, then copy or share the result.

Use plantable area, target stems, survival rate, and supplement rate to estimate the number of seedlings.

Area / Target stems

Area × density

Survival rate / Supplement rate

Survival / supplement

Square-equivalent reference only.

Global-ready

Sample cases

Input

1 ha planting block

Area 1 ha, target stems 1,100 stems/ha, survival 90%, supplement 5%

Output

Target stems 1,100, seedlings before supplement 1,223, supplement reserve 62, required seedlings 1,285, spacing 3.02 m

Input

5 acre planting block

Area 5 acre, target stems 600 stems/acre, survival 85%, supplement 5%

Output

Target stems 3,000, seedlings before supplement 3,530, supplement reserve 177, required seedlings 3,707, spacing 8.52 ft

Glossary

Target stems

The planned final stand per hectare or acre before survival and supplement assumptions are applied.

Survival rate

The share of planted seedlings expected to survive to establishment.

Supplement rate

An extra percentage added on top of the survival-adjusted base to cover replacements and other losses.

Spacing

A square-equivalent spacing derived from density only.

Plantable area

The area that can actually be planted after excluding roads, buffers, waterways, and other non-planting parts.

Established stems

The stems expected to remain after survival and supplement assumptions are applied.

Formulas

The calculator converts all area and density inputs internally, then applies rounding where needed.

  1. Target stems = ceil(area × density)
  2. Seedlings before supplement = ceil(target stems ÷ survival ratio)
  3. Supplement reserve = ceil(seedlings before supplement × supplement ratio)
  4. Required seedlings = seedlings before supplement + supplement reserve
  5. Approx. spacing = sqrt(1 ÷ density per m²)
  6. Area per tree = 1 ÷ density per m²

FAQ

What does target stems mean?

It is the planned stand density after establishment, before survival and supplement assumptions are applied.

What is the difference between survival and supplement?

Survival is the share of planted seedlings expected to establish. Supplement is the extra buffer ordered on top of the survival-adjusted base.

Why is the spacing square-equivalent only?

The calculator derives spacing from density only. Real field layouts may be rectangular, staggered, or adjusted around roads, buffers, and edges.

Can I mix hectare and acre inputs?

Yes. Area and density units are converted independently, so you can mix the units that best match your source data.

Why are subsidies not included?

Because this tool stays focused on pure count calculations. Grants and administrative rules vary by country and program.

Important notes

  • Use plantable area, not gross site area.
  • The spacing shown here is a square-equivalent reference only.
  • Survival and supplement assumptions vary by species, site quality, nursery stock, and planting season.
  • Grants, subsidies, and administrative formulas are intentionally out of scope.