Groups are usually arranged by a computer program and provide a classification from associations. The number of individual species are counted in each quadrat. Density is expressed as the number of individuals per unit area. Occurrences for each species are summed and divided by the total number of points. Quadrats are located side by side, with a smaller quadrat located within a large quadrat.
Frequency is the percentage of quadrats in which a species is recorded.
The optimum frame size for each species should provide a frequency value between 0.2 and 0.8. Density Frequency Frequency - used to determine vegetation condition and trend. Provides a direct count of individuals per unit area. Quick estimate of species composition. Reduces surveyor bias from pin placement.