Coombe Hill Hollow is a biological

Site of Special Scientific Interest A Site of Special Scientific Interest (SSSI) in Great Britain, or an Area of Special Scientific Interest (ASSI) in the Isle of Man and Northern Ireland, is a conservation designation denoting a protected area in the United Kingdom and Isle ...

north of

Sibbertoft Sibbertoft is a village and civil parish in West Northamptonshire in England. At the time of the 2001 census, the parish's population (including Sulby) was 343 people, increasing to 462 at the 2011 Census. The village's name means 'curtilage o ...

Northamptonshire Northamptonshire ( ; abbreviated Northants.) is a Ceremonial counties of England, ceremonial county in the East Midlands of England. It is bordered by Leicestershire, Rutland and Lincolnshire to the north, Cambridgeshire to the east, Bedfordshi ...

, England. This steep narrow valley has neutral grassland which has never been subject to fertilisers or herbicides, and it has diverse flora. Grasses include brown bent,

red fescue ''Festuca rubra'' is a species of grass known by the common name red fescue, creeping red fescue or the rush-leaf fescue. It is widespread across much of the Northern Hemisphere and can tolerate many habitats and climates. It is best adapted to w ...

, Yorkshire fog and

crested dog's-tail ''Cynosurus cristatus'', the crested dog's-tail, is a short-lived perennial grass in the family Poaceae, characterised by a seed head that is flat on one side. It typically grows in species rich grassland. It thrives in a variety of soil types ...

. Lime-rich areas have harebell and mouse-ear hawkweed, and there are locally important butterfly populations. Other habitats include bramble, gorse and woods. The site is private land with no public access.

References

{{SSSIs Northamptonshire Sites of Special Scientific Interest in Northamptonshire