Originally Posted by
Stamp
I sympathise with you, Sitka is a species which will naturally regenerate given the right conditions. Now they are there it will be almost impossible to remove them completely, Sitka is planted over here but doesn't cause any problems (other than the Desert effect!). We get similar problems with Hemlock in plantations, they regenerate so quick and block out the light for anything else.
I'm not familiar with the topography of Norway but over here we have heathlands, moorlands etc. that we protect and stop trees from growing. The problem is we are stopping nature from reclaiming land to its natural form, these heathlands are man made, we cleared them for timber (not all but a lot) and now have a nativised environment which we protect from returning to woodland. As soon as we start introducing species or removing them nature loses control of the natural order. I fear you are fighting a losing battle against the spruce.