Greening the Desert - Feral: Rewilding the Land, the Sea, and Human Life - page 74

qualified as a wood, and it was already hard to picture the sheep pas-
ture that had preceded it.
They had planted trees, but soon discovered that, in much of the
fenced land, this was unnecessary. Where they had turned over the
turf, the exposed soil was colonized by birch seed, which blew in from
a few surviving trees further down the valley, which had themselves
returned, Ritchie explained, as a result of an agricultural depression
around a century ago.
'Almost every tree we planted has now been overwhelmed by native
birch. It grew so densely it looked like the cress you grow on your
windowsill. Even when the trees we planted survived, the local birches
did much better. They're genetically suited to this site. Seeing the way
the birch recolonized was a real awakening. I saw that nature is far
more adept at doing these things than we are.'
Ritchie's experiments, which became the basis of his master's dis-
sertation, demonstrated that birch could be sown, with the help of
some scraping of the soil and hacking of the ferns, into dense bracken,
without the need for herbicides.
'It's all about soil disturbance with birch. It's designed to chase
retreating glaciers and ice sheets by seeding into the exposed soils
before the coarse grass gets a foot in the door. It's also good at recolo-
nizing burnt sites and places where the conifers have been felled. You
just need to prepare the site with a tractor or a rotovator. Or you
could use cattle or pigs or wild boar to break up the bracken and dis-
turb the soil. If we're serious about getting forests back in the uplands
as quickly as possible, this has to be a way to go. It could work out a
lot cheaper than planting and weeding nursery stock.'
In the acid hills, he told me, birch, with its slightly alkaline leaf lit-
ter, prepares the soil for other trees. At the foot of the twisted black
and white trunks, orange toadstools - birch boletus - grew. They
looked like soggy bread rolls, or, in the green rockpool light beneath
the trees, like sea sponges. They pushed their way through dead leaves,
deep moss, bilberry and little ferns. In some places the big soft leaves
of foxgloves flopped over the ground. It was hard to grasp that this
land had belonged to the Desert just twenty years before.
We scrambled across the slope until we reached a treacherous band
of exposed rock, over which grew algae and slimemold, like the first