Up till the 1960s it was common practice for the State Forestry Service to plant conifers on the heathlands in the Netherlands. As a result, heaths and sand-dunes disappeared and with them the characteristic heathland butterflies like the Tree Grayling (Hipparchia statilinus), Silver-studded Blue (Plebeius argus) and Heath Fritillary (Melitaea athalia). In the past couple of decades, a change of management in the way of tree-felling, mowing and grazing has restored the original biotope. On the heath of the Kootwijksche Veld (province Gelderland) this improved management has led to an increase in the number of Silver-studded Blues.