Calcareous
Total area in Lincolnshire (approx.): 142ha
Total area within Critical Natural Asset & Basic Natural Stock Sites (approx.): 10ha in 5 sites.

Lincoln lies in a broad gap created in the Jurassic limestone uplands by the River Witham. North of the city the limestone forms a narrow ridge with a steep western scarp whilst to the south it widens into a broad plateau.
There are only four sites identified as Critical Natural Asset or Basic Natural Stock which contain substantial areas of limestone grassland in Lincoln (Greetwell Hollow; South Common; Dean and Chapter Quarry; Old Quarry). However none of these patches of calcareous grassland exceeds 4 ha. Small fragments of calcareous grassland occur under scrub and in other old quarries but are too small to be accurately measured. However new chalk and limestone exposures ( for example those at Greetwell Hollow Quarry) provide opportunities for colonisation by specialised plants, although few are old enough to have developed the characteristics and ecosystem of ancient grassland.