Scrub Clearance on Portsdown Hill
Manual Scrub clearance
For the past decade, volunteers armed with bowsaws, lopers and billhooks have been clearing scrub from the hill, trying at least to stop it spreading even further. Although machinery now helps, hand-clearance continues in many places inaccessible to the machinery, such as along fence-lines, in trenches, and on particulary steep slopes.
Furthermore, where light scrub appears in grassland it can be removed by hand with less damage than using heavy machinery. People are also more likely to see destructive metal waste and valuable plants and animal homes than are flail teeth.
The scrub consists mainly of hawthorn, blackthorn and buckthorn bushes, with much privet, clematis and bramble. Larger trees such as white beam and sycamore also becoming established. The preponderance of 'thorn' in the species list indicates some of the problems we face. Most (sensible) volunteers use chainsaw helmets when attacking thick scrub, and protective clothing is advisable.
Photos of scrub-clearance are not easy to take - it is difficult to represent the problem, even with "before and after" images.
Root removal
Not only must the scrub be chopped off the top, but whenever possible, the roots should be dug out.
Tim digging up roots with a mattock
Maretta uprooting a hawthorn with a fork. The hawthorn was later transplanted elsewhere as part of a hedge.
Ben digging roots with his mini-digger
Volunteers at work
Mechanical Scrub Clearance
With the assistance of machinery, the scrub can be got through much quicker
Tractor pulling up stump
Aebi flailing scrub
Mower clearing regrowth
Excavators
Excavators can rip out large areas of scrub, roots included, and leave a site ready for recolonisation with downland species. The bushes and roots are best shredded for removal to composting site. This is an expensive operation but the quickest way of getting rid of scrub. It is used on the densest scrub – with caution.
Forestry Mulcher
This machine shreds the bushes and quickly opens up the landscape. The flailed material has to be collected for disposal off site. The stumps are left in the ground and will encourage the regeneration of scrub if not managed to prevent this. This means long-term mowing and/or spot treatment with herbicide. Ground disturbance is negligible and any grassland species within the scrub can quickly benefit from the access to light.
Spot-poisoning
Although we pull out roots whenever possible, regrowth is relentless. Until we get continual grazing, this can best be controlled with spot-poisoning, by either painting freshly-cut scrub stalks, or careful spraying.
