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Canopy Cover

Canopy cover or crown cover describes the area represented by the vertical projection of plant foliage onto the ground. Canopy cover is determined as the perimeter of the plant at its widest horizontal plane. It generally assumes that small gaps within the foliage are included and an average crown perimeter is imagined to smooth irregular edges.

References and Further Reading

Daubenmire, R. 1968. Plant communities: A textbook on plant synecology. Harper Row, New York, NY. pp 42-43.

Browse

Browse is the biomass from trees, shrubs, and woody vines that is available for consumption by livestock and wildlife. It includes leaves and small twigs, but excludes branches and trunks that would not be consumed. Browse is also generally restricted to species or parts of plants deemed palatable to animals, but this issue is confused by the subjective nature of palatability and alternative forage sources.

Methods to Determine Biomass

Biomass can be determined using either direct or indirect sampling methods. Direct methods involve techniques that weigh or estimate the actual biomass of plants in quadrats. Indirect methods are based on developing a relationship between plant weight and an easier-to-measure attribute such as plant height, rainfall, or cover.

Biomass

Biomass is a commonly measured vegetation attribute that refers to the weight of plant material within a given area. Other general terms, such as 'yield' or 'production', are sometimes used interchangeably with biomass. Units to express biomass should be selected so that actual plant weight is easy to visualize, such as lb/acre, kg/ha or g/m² according to vegetation abundance and objectives of the inventory or monitoring program.

Estimation Approaches to Determine Biomass

Estimation approaches involve techniques that require observers to visually assess biomass in quadrats, rather than harvesting to determine biomass. Three common estimation methods to determine biomass are commonly used: