Rough Hills is a series of grasslands, approximately 2 ha in size, situated within Sailor's Grove. It has been identified as a Local Wildlife Site for its species-rich neutral grassland interest.
The area was known as grassland from before 1838. Prior to the 1960s land use was mixed arable and pasture, and since the 1960s have a history of irregular cutting, abandoned mowing experiments and haphazard management for various reasons. Inconsistent management led to the substantial scrub encroachment. From 1970 aerial photographs, the grasslands reduced about twice in size, and are now surrounded by mature hawthorn, crab apple and ash trees. Since 2013, a diverse mowing regime has been implemented accompanied by regular monitoring of plant species composition.
Plant species composition
Between 2013 and 2020, 122 species of flowering plants were recorded at Rough Hills. According to Herts and Middlesex Wildlife Trust (HMWT) criteria, 28 of these species are positive grassland indicators, 19 are negative grassland indicators and 7 are Ancient Woodland Indicators (Mashanova et al. 2021).Click here for the full species list with their indicator status.
The most notable species include Adder’s-tongue (Ophioglossum vulgatum) and two orchids – Bee Orchid (Ophrys apifera) and Common Spotted-orchid (Dactylorhiza fuchsii). Adder's-tongue is a fern associated with unimproved grasslands and lost from many sites in Hertfordshire.
Abundant species include Meadow Buttercup (Ranunculus acris) and Hedge Bedstraw (Galium album) in mid-summer, and Hoary Ragwort (Senecio erucifolius) and Knapweed (Centaurea nigra agg.) in late summer. Hedge Bedstraw is a common plant of hedgerows and ungrazed grasslands and has become abundant in Rough Hills following re-introduction of regular mowing. Hoary Ragwort and Knapweed play important role in providing food for invertebrates late in the season. Meadow Cranesbill (Geranium pratense) and Marjoram (Origanum vulgare) have been spreading steadily during the observation period.
