Ham Hill is a hill and area of chalk downland in Wiltshire, England, on the steep banks running alongside the road from the village of Ham to Buttermere, close to the Berkshire border. A biological Site of Special Scientific Interest, notified in 1971, covers 1.5

hectare The hectare (; SI symbol: ha) is a non-SI metric unit of area equal to a square with 100-metre sides (1 hm2), or 10,000 m2, and is primarily used in the measurement of land. There are 100 hectares in one square kilometre. An acre is a ...

s of the site; this designation is due to the site's species-rich plant and insect communities, which include some rare species. Notable among these is the musk orchid (''Herminium monorchis''), which has been confirmed at only one other site in Wiltshire. The site is managed as a

nature reserve A nature reserve (also known as a wildlife refuge, wildlife sanctuary, biosphere reserve or bioreserve, natural or nature preserve, or nature conservation area) is a protected area of importance for flora, fauna, or features of geological or ...

by Wiltshire Wildlife Trust. It is managed by grazing with sheep to prevent scrub encroachment and takeover by rank vegetation, which would otherwise crowd out the scarce plant species.Ham Hill Nature Reserve
Wiltshire Wildlife Trust (accessed 1 March 2022)

Biological interest

The hillsides at this site have short, herb-rich grassland, and the flatter areas, taller vegetation. The main species in the plant communities here are upright brome (''Bromus erectus''),

sheep's fescue ''Festuca ovina'', sheep's fescue or sheep fescue, is a species of grass. It is sometimes confused with hard fescue (''Festuca trachyphylla''). General description It is a perennial plant sometimes found in acidic ground, and in mountain pastur ...

(''Festuca ovina''),

quaking-grass ''Briza'' is a genus of annual and perennial plants in the grass family, native to northern temperate regions of Eurasia, North Africa, and certain islands in the Atlantic. The group is generally referred to as the quaking grasses because the ...

(''Briza media''), and downland herbs such as burnet-saxifrage (''Pimpinella saxifraga''), salad-burnet (''Sanguisorba minor''),

common milkwort Common milkwort is a common name for several plants and may refer to: *'' Polygala sanguinea'', native to eastern North America *''Polygala vulgaris ''Polygala vulgaris'', known as the common milkwort, is a herbaceous perennial plant of the genu ...

(''Polygala vulgaris'') and dwarf thistle (''Cirsium acaule'').Natural England citation sheet for the site
(accessed 1 March 2022) Other plant species found include

squinancywort ''Asperula cynanchica'', the squinancywort or squincywort, is a species of flowering plant in the family Rubiaceae. Its common name is derived from its former use as a medicinal herb to cure quinsy. It is native to much of southern and central ...

(''Asperula cynanchica''). A wide range of typical chalk downland specialists are found at Ham Hill including

clustered bellflower ''Campanula glomerata'', known by the common names clustered bellflower or Dane's blood, is a species of flowering plant in the genus '' Campanula'', belonging to the family Campanulaceae. It is the county flower of Rutland, England. Etymology ...

(''Campanula glomerata''),

autumn gentian ''Gentianella amarella'', the autumn gentian, autumn dwarf gentian, or autumn felwort, is a short biennial plant flowering plant in the gentian family, Gentianaceae. It is found throughout Northern Europe, the western and northern United States ...

(''gentianella amarella''),

chalk milkwort ''Polygala calcarea'', the chalk milkwort, is a species of flowering plant in the family Polygalaceae, native to western Europe. It is a delicate mat-forming evergreen perennial growing to tall by broad, with spikes of small, vivid deep blue fl ...

(''Polygala vulgaris''), horseshoe vetch (''Hippocrepis comosa'') and common rockrose (''Helianthemum nummularium''). Both

(''Campanula glomerata'' and

(''gentianella amarella'') are abundant. This is one of only two confirmed sites in Wiltshire for musk orchid (''Herminium monorchis'').Pilkington, Sharon (2007) Wiltshire Rare Plant Register (The rare and threatened vascular plants of North and South Wiltshire) Seven other species of orchids are presented including frog orchid (''Coeloglossum viride''),

burnt orchid ''Neotinea ustulata'' (syn. ''Orchis ustula''), the burnt orchid or burnt-tip orchid, is a European terrestrial orchid native to mountains in central and southern Europe, growing at up to elevation. The plant is considered Endangered in Great Br ...

(''Orchis ustulata'') and

fragrant orchid ''Gymnadenia conopsea'', commonly known as the fragrant orchid or chalk fragrant orchid, is a herbaceous plant of the family Orchidaceae native to northern Europe. Etymology The name of the genus ''Gymnadenia'' is formed from Greek words (', ...

(''Gymnadenia conopsea''). Chalk-grassland bryophytes found here include the liverwort ''

Leiocolea turbinata ''Leiocolea turbinata'' is a species of liverwort belonging to the family Jungermanniaceae ''Jungermanniaceae'' is the namesake family of leafy liverworts. It is a group of small plants that are widely distributed. Several genera formerly in ...

'' and the mosses ''

Ctenidium molluscum ''Ctenidium molluscum'' is a species of moss belonging to the family Hypnaceae Hypnaceae is a large family of moss with broad worldwide occurrence in the class Bryopsida, subclass Bryidae and order Hypnales. Genera include ''Hypnum'', '' Phyll ...

'', ''

Dicranella varia ''Dicranella varia'' is a species of moss belonging to the family Dicranaceae Dicranaceae is a family of haplolepideous mosses (Dicranidae) in class Bryopsida. Species within this family are dioicous Dioicy () is a sexual system where ar ...

'', ''

Weissia microstoma ''Weissia microstoma'' is a species of moss belonging to the family Pottiaceae The Pottiaceae are a Family (biology), family of mosses. They form the most numerous moss family known, containing nearly 1500 species or more than 10% of the 10,00 ...

'' and ''

Entodon concinnus ''Entodon concinnus'' is a species of moss belonging to the family Entodontaceae. It has cosmopolitan distribution In biogeography, cosmopolitan distribution is the term for the range of a taxon that extends across all or most of the world ...

''. A colony of the Duke of Burgundy butterflies (''Hamearis lucina'') is present and other butterfly species associated with chalk flora include

green hairstreak The green hairstreak (''Callophrys rubi'') is a small butterfly in the family Lycaenidae. Etymology The genus name '' Callophrys'' is a Greek word meaning "beautiful eyebrows", while the species Latin name ''rubi'' derives from ''Rubus'' (bramb ...

(''Callophrys rubi''),

dingy skipper The Dingy Skipper (''Erynnis tages'') is a butterfly of the family Hesperiidae. Description ''Erynnis tages'' is different from other skippers because of the predominantly monochrome, gray-brown wing coloration and the marbling, which is only ...

(''Erynnis tages''), dark green fritillary (''Argynnis aglaja'') and chalkhill blue (''Lysandra coridon''). The

Roman snail ''Helix pomatia'', common names the Roman snail, Burgundy snail, or escargot, is a species of large, edible, air-breathing land snail, a pulmonate gastropod terrestrial mollusc in the family Helicidae.MolluscaBase eds. (2021). MolluscaBase. ...

(''Helix pomatia''), the largest snail species to be found in Britain, occurs here.

References

External links

Ham Hill
- Wiltshire Wildlife Trust
Natural England website
(SSSI information) {{SSSIs Wilts biological Hills of Wiltshire Sites of Special Scientific Interest in Wiltshire Sites of Special Scientific Interest notified in 1971 Wiltshire Wildlife Trust reserves