The Ryedale part of the Yorkshire Wolds still holds some 300 hectares of natural chalk grassland, mainly on steep-sided valley slopes grazed by sheep or cattle. This type of grassland is enormously important for wildlife and is identified as a Priority Habitat in both the local and national Biodiversity Action Plans. A key feature is the rich flora of lime-loving herbs and grasses - up to 30 different species can be found in a single square yard of turf. Many unusual and attractive insects depend upon the wildflower-rich grassland including rarities such as the Chalk Carpet moth and the Rockrose Leaf Beetle.
Tor-grass is a native chalk grassland plant but in recent years it has become increasingly dominant in many dales. Unfortunately, this vigorous, tussocky grass rapidly smothers out less competitive plants like rockrose, cowslip and salad burnet. Not only does this result in a loss of wildlife interest, but it also reduces the forage value of the grassland because very few livestock will eat its tough foliage.
The spread of tor-grass probably results from a combination of different factors. It is responsive to nitrogen and may have been encouraged by atmospheric pollution, though changes in grazing patterns must also have played a part. As traditional livestock farming has become less profitable, grazing pressure has been reduced whilst there are fewer ‘hard mouthed’ animals around to keep tor-grass under control.
Tor-grass can be kept in check by grazing hard in spring when the new shoots are emerging. However, this is often impractical because valley pastures almost always include better grassland which stock will concentrate on. One solution which may benefit both wildlife and farmers is to supplement grazing by farm livestock with hardy native ponies which will tuck into tough vegetation with gusto. The Exmoor Pony, in particular, has established a reputation as an effective browser on tor-grass, with Exmoors already in use on several chalk grassland nature reserves.
A trial has begun near Thixendale to see if Exmoor Ponies are practical to use on a wider scale for managing chalk grassland. This project has been organised by Julian Small of EPIC (Exmoor Ponies In Conservation). If successful, it is hoped to make Exmoors available for grazing other chalk grassland sites on the Wolds to supplement grazing by farm stock.
For further information on EPIC in Yorkshire, contact: firstname.lastname@example.org