# Canopy closure

n. The proportion of the sky hemisphere obscured by vegetation when viewed from a single point (Jennings and others 1999).

• Discussion

Canopy closure is a point estimate of the coverage of a forest canopy, and is measured in the field with a spherical densiometer (also called a mirror optometer) or by analyzing upward-looking hemispherical photographs. Canopy closure is almost always greater than canopy cover measured at the same point.

Canopy closure is not synonymous with the silvicultural term crown closure.

•

Canopy closure is most commonly expressed as a percent of ground area, but may in some papers be expressed as a fraction. Multiply the canopy cover fraction by 100 to express it as a percent.

• References

Jennings. 1999.

• Notes

• Joe Scott, Research Forester

Systems for Environmental Management