Photo: Marina Smith
The habitat value of some types of open ground can be maintained or enhanced by grazing or mechanical forms of cutting.
Grazing animals can stop vegetation from getting too rank, prevent the build-up of a dense litter layer and slow down the tendency to scrub over with shrubs and trees. Their dung and bare hoof-prints provide micro-habitats for certain invertebrates and plants. Mechanical treatments can be costly and provide no financial return whereas grazing can in some cases be leased out to provide income. It is an attractive option for woodland owners and managers looking to improve the open habitats in their woods.
Forest Research is working with Forestry Commission Scotland and Scottish Natural Heritage to monitor a trial of cattle grazing on moorland in Minard Forest, Argyll. The open moorland is surrounded by mature forest but has not been used for stock grazing since the forest was planted.
Conservation of black grouse is a high priority at Minard because this bird has suffered a severe decline in Argyll and the remaining populations are mostly centred in and around forests. Moorland areas within these forests are normally managed to benefit black grouse by cutting strips through rank heather with a tractor and mechanical flail. This benefits black grouse by opening up routes through the heather and promoting the growth of young shoots of heather and blaeberry on which they feed.
The cattle grazing trial will show how effective cattle are, not only at opening up and rejuvenating heather and blaeberry but also at improving the grassy areas used for lekking and the flush and bog habitats used for foraging by black grouse chicks. The composition and structure of the vegetation and abundance of invertebrates that form the main diet of the chicks is being monitored. The grazed sites are being compared with ungrazed exclosures to highlight the effect of the cattle.
For further information about this work please contact Russell Anderson.