|Number of grid squares with land area in Montgomeryshire|
|10 km: 36 squares||Tetrad (2 km): 589 squares|
For the purposes of the field survey for the Flora of Montgomeryshire, species were categorized, on the basis of earlier information, as follows:
|Category||Estimated Distribution||Number of species||Precision for Recording|
Total number of species recorded since 1970: 1089
Mapped species: these are the A species at 10 km precision, and the B species plus 87 of the more frequent C species at 2 km precision.
Coincidence Map showing the Species Richness of Tetrads in Montgomeryshire
(The map is based on the 539 mapped B and C species only)