What next for botanical recording?
Shropshire Botanical Society Newsletter - Spring 2000 - page 5
During the last few decades there have been a number of significant mile-stones in botanical recording in Britain, starting with the Atlas of the British Flora in 1962, and culminating in Flora 2000 for which many botanists have been collecting records in the last few years. Between the two, a major local achievement was the Ecological Flora of the Shropshire Region, which in my opinion remains one of the most interesting local floras nearly fifteen years after its publication in 1985. One of the reasons that the Shropshire Flora is of particular interest is revealed by the title: as well as the usual distribution maps and comments on species distribution, there is a wealth of information on the ecology of the plants and their habitats, and on associated plant species.
Recording for all these publications was done on either a tetrad or hectad (10km square) basis. This has the advantage that the records can be easily and consistently mapped. It has the disadvantage that, by itself, it does not permit any analysis of abundance within the recording unit, and does not reveal associations between species or other useful ecological data. There is no doubt that comparison of the maps in Atlas 2000 with the 1962 Atlas will show some drastic and interesting changes. However, much of the useful information gathered by recorders in the course of their observations is in effect lost by this coarse-scale mapping.
Many botanists enjoy "square-bashing", watching the records mount up towards some target figure. And of course, some squares are much richer than others. The reasons are usually clear to the recorders. A range of geological formations, in particular the presence of limestone, and the presence of a wide variety of habitats, will greatly increase the number of wild plants present. Additionally, the way in which those habitats are managed will also influence the number and abundance of plant species. The reasons for the changes between the early 1960s and the 1990s will largely be connected with the change in habitat types (overwhelmingly a decline in semi-natural habitats) and the change in the way they are managed (more intensive management in some cases, neglect in others).
Now that the recording for Atlas 2000 is complete, many field botanists will be looking for a new challenge. It seems to me that the most useful thing we could do locally would be to switch our future recording from a tetrad or hectad basis to an ecological one. The unit of recording would then be a discrete area of semi-natural vegetation. Many of these areas would be known "sites" in the sense of SSSIs or Shropshire Trust Wildlife Sites, and these are precisely the locations which hold the most species and which are most in need of good, up-to-date records to assist in the job of management planning. To ensure the most useful and complete records, two things would be necessary: an idea of the abundance of the less common species, and information on the vegetation with which the species are associated. Both of these should preferably be collected in a recognised, standard way. The publication of the volumes of the National Vegetation Classification in recent years provides a standard method for recording vegetation, and would, I believe be a useful adjunct to the recording of species and their abundance. In most cases, it is fairly easy to transfer the data thus recorded to a tetrad map if that's needed.
Changing to a site-based recording method need not discourage people from wandering the countryside looking for unexpected plants. It would be foolish to suppose that there is nothing left to discover, and for many of us, finding something that is not already known about is a major attraction of botanising. However, some basic information on the habitat and the associate species would tell us more about the plant and its prospects, and would be of greater scientific value than a list or a dot on a map.
Perring, F. H., and Walters, S.M. (eds), 1962; Atlas of the British Flora BSBI/Thomas Nelson
Sinker, C. A., Packham, J. R., Trueman, I. C., Oswald, P. H., Perring, F. H. and Prestwood, W. V., 1985; Ecological Flora of the Shropshire Region; Shropshire Trust for Nature Conservation.
Rodwell, J. 1991-2000. National Vegetation Classification; Cambridge University Press