Surrey Botanical Society

Monad Records by Date Class

Analyses of the numbers of the Surrey Botanical Society (SBS) MapMate records and taxa was carried out to investigate which monads in Surrey had the fewest records and taxa in order to target them for future recording.

Surrey covers 2,105 monads, including 1,822 complete monads, 145 with 50% to 99.9% coverage and 138 with 0.1% to 49.9% coverage. The number of records of Vascular Plants and Charophytes recorded by the SBS in MapMate as at 29th February, 2014 stood at 444,329, although 2,296[1] of these records were not included in the analyses by monad (see Table 1).

A list of monads and the percentage of each 1km square in Surrey was copied from the Biological Records Centre and imported into a MS Access table. The analyses of records and taxa for each Date Class and all years were carried out in MS Access using queries developed for the purpose (see Appendix 2 for records & Appendix 3 for taxa) using the list of Surrey monads and SBS MapMate data


Length of OS GridRefOS GridRef TypeNumber of OS GridRefsPercentage of OS GridRefs
0Blank60.001
4Hectads - 10km Square2,5370.573
5Tetrads - 2km Square8,5531.935
Subtotal (not mapped)11,0962.509
6Monads - 1km Square91,50620.701
8100m Square332,53575.228
1010m Square6,8041.539
121m Square920.208
Subtotal (mapped)430,93797.489
Total records442,033100
No Taxon10
Taxon 'Not present'765
Deleted records1,308
Duplicate records*213
Total444,329
Table 1. Summary of Mapmate records by OS Grid Reference * = same Taxon, same Monad, same Date Class

Six records where the OSGridRef was null; 2,537 hectad records and 8,553 tetrad records were not included in the analyses by monad.

[1]Ten records without a Taxon; 765 records where the Taxon was recorded as 'Not present'; and 1,308 deleted records were not included in the analyses by monad. The analyses also revealed 213 duplicate records with respect to Taxon, Monad and Date Class.

The majority of the records (430,937 or c .97.5%) are at a sufficient precision to enable analyses at the monad (1km Square) level (Table 2)


Date ClassYear RangeRecordsTaxaCumulative no.
of distinct taxa
DC 01666-1929417196196
DC 11930-19698,1321,2301,268
DC 21970-198615,7421,5621,752
DC 31987-199968,1672,0232,287
DC 42000-2009150,9151,9812,528
DC 52010-2019187,5641,9662,746
Totals1666-2019430,9372,7462,746
Table 2. Summary of MapMate records and taxa by Date Class (Year Range). N.B. The Date Classes are historical and not intended to allow comparison between the number of records for each class.

The analyses revealed 80 monads without any records or taxa and an additional 267 monads with fewer than 20 records (1666-2019).

The data were also used to populate Interactive Google maps developed by our webmaster expressly for the purpose. These maps enable users to search for a grid reference or place name and select whether to display the number of records or taxa in every Surrey monad by date classes. Thanks is also due to the members whose efforts in the field made this project possible.

Download Records Analysis Spread Sheet | Download Taxa Analysis Spread Sheet