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A method of describing an area of vegetation devised by J. Braun-Blanquet in 1927. It is used to survey large areas very rapidly. Two scales are used. One consists of a plus sign and a series of numbers from 1 to 5 denoting both the numbers of species and the proportion of the area covered by that species, ranging from + (sparse and covering a small area) to 5 (covering more than 75% of the area). The second scale indicates how the species are grouped and ranges from Soc. 1 (growing singly) to Soc. 5 (growing in pure populations). The information is obtained by laying down adjacent quadrats of increasing size. One of a number of variations of Braun-Blanquet's method is the Domin scale, which is more accurate as there are more subdivisions of the original scale. The Braun-Blanquet scale also included a five-point scale to express the degree of presence of a plant. For example, 5 = constantly present in 80-100% of the areas; 1 = rare in 1-20% of the areas.
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