THE GHYLL The Ghyll is a 42 acre Local Nature Reserve composed mainly of Ancient Semi Natural Woodland (ASNW) that encompasses a steep-sided wooded valley carved out by a stream flowing from the north at Silver Jubilee Recreation Ground, down to Jarvis Brook Recreation Ground in the south. Lime Kiln Playing Fields are located to the east Parts of the site are more open and resemble the lowland heathland of nearby Ashdown Forest with its sunny banks of gorse and ling. Ghyll woodlands are important for biodiversity in Sussex because the steep-sided valleys create an almost unique microclimate with high humidity and a low frost incidence. Rare flora including ferns, mosses and liverworts can be found in these conditions.