St. Leonard's Forest

Also within

West Sussex County High Weald Scenic Area

Condition (Natural England)

Habitats

Bracken scrub, Carr

Birds & fish recorded

Birds

Description

Area, 84.5 ha. 208.8 ac. Description This site includes the remnants of a formerly more extensive deciduous forest on the Tunbridge Wells Sands Hastings Beds 3km east of Horsham. Examples of high forest remain and the ground vegetation is still varied and the streams which cross the site retain relict flora from the ‘Atlantic’ period of same 5000 years ago. The woodland bird population is varied and includes some of the more local species of old woodlands. The woodlands also support a population of the purple emperor Apatura iris, a butterfly with a restricted British distribution. Much of the deciduous woodland is dominated by pedunculate oak Quercus robur with silver birch Betula pendula, common birch Betula pubescens and beech Fagus sylvatica. The shrub layer includes holly Ilex aquifolium and hazel Corylus avellana with hawthorn Crataegus monogyna, blackthorn Prunus spinosa and guelder rose Viburnum opulus. Also included in the site are areas of conifer plantation, largely consisting of Scot's pine Pinus sylvestris and Corsican pine Pinus nigra. The ground flora of the deciduous woodland is dominated by bracken Pteridium aquilinum, bramble Rubus fruticosus and honeysuckle Lonicera periclymenum, with bluebell Hyacinthoides non-scripta, primrose Primula vulgaris and common violet Viola riviniana. At Lilybeds there is a large colony of wild lily of the valley Convallaria majalis. In the more open areas of woodland and along the rides in the plantations, species characteristic of heathland occur including ling Calluna vulgaris, cross leaved heath Erica tetralix and ivy leaved bellflower Wahlenbergia hederacea. The humid microclimate of sheep wash gill has enabled the ‘Atlantic’ bryophytes mosses and liverworts Hookeria lucens and Hyoconium flagellare to survive. The presence of these plants indicate the continuity of woodland cover at this site for the past 5000 years. The damp areas adjacent to the gills have stands of alder Alnus glutinosa with common sallow Salix cinerea. Along the edge of Hawkins pond damp woodlands grade through alder and willow carr to emergent vegetation dominated by reed mace Typha latifolia with water plantain Alisma plantago-aquatica, bulrush Schoenoplectus lacustris and bladder sedge Carex vesicaria. Hawkins pond itself is largely free of floating vegetation although in the shallow areas there are rafts of broad leaved pondweed Potamogeton natans, yellow water lily Nuphar lutea and water crowfoot Ranunculus peltatus. The rare moss Micromitrium tenerum has been recorded on patches of drying mud, while the rare liverwort violet crystalwort Riccia huebeneriana also occurs in the pond. The woodlands support populations of the rare purple emperor butterfly Apatura iris and a diversity of woodland breeding birds including all three British woodpecker, nightjar, redstart and wood warbler.

Species mentioned

Insects to look out for

These moths, butterflies and beetles are known to feed on plants recorded at this site, and carry a notable UK conservation status — but a host-plant being present doesn't mean the insect has actually been recorded here. Treat this as "worth watching for," not a confirmed sighting.

Host-plant data: Cook et al. (2025), Traits data for the butterflies and macro-moths of Great Britain and Ireland, 2024, UK Centre for Ecology & Hydrology / Butterfly Conservation; and Padovani et al. (2020), Database of Insects and their Food Plants (DBIF), UK Centre for Ecology & Hydrology (both Open Government Licence). Contains data supplied by UK Centre for Ecology & Hydrology.

Plant communities