Coombe Hill Hollow is a biological Site of Special Scientific Interest 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 county in the East Midlands of England. In 2015, it had a population of 723,000. The county is administered by two unitary authorities: North Northamptonshire and West Northamptonshire. It is ...

. 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 or creeping red fescue. It is widespread across much of the Northern Hemisphere and can tolerate many habitats and climates. It is best adapted to well-drained soils in ...

Yorkshire fog ''Holcus lanatus'' is a perennial grass. The specific epithet ' is Latin for 'woolly' which describes the plant's hairy texture. Common names include Yorkshire fog, tufted grass, and meadow soft grass. In North America, where it is an invasive sp ...

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 ''Campanula rotundifolia'', the harebell, Scottish bluebell, or bluebell of Scotland, is a species of flowering plant in the bellflower family Campanulaceae. This herbaceous perennial is found throughout the temperate regions of the northern hemi ...

and

mouse-ear hawkweed ''Pilosella officinarum'' ( synonym ''Hieracium pilosella''), known as mouse-ear hawkweed, is a yellow-flowered species of flowering plant in the daisy family Asteraceae, native to Europe and northern Asia. It produces single, lemon-coloured infl ...

, 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