Arable weeds of the Scottish Borders

Many years of fieldwork have led the authors to hypothesise that there is a single relatively species-rich arable weed community present across the Scottish Borders that is best expressed in broad-leaved root crops and in set-aside on imperfectly-drained soils, while the species-poor communities typically found in cereal crops are a degraded form of this. 102 samples have been studied to test this hypothesis and to search for a community typical of slightly calcareous well-drained soils. The community typical of imperfectly-drained soils has been defined and is considered to be a species-rich variant of the NVC OV13 Stellaria media-Capsella bursa-pectoris open habitat community. Species typical of well-drained soils have been shown to be scarce and not to form a distinct community, though they may well have done so in the past.