Rewilding two UK fields

 From ZME Science:

With no special equipment, no fences, and no watering, two abandoned agricultural fields in the UK have been rewilded, in large parts due to the efforts of jays, which virtually “engineered” these new woodlands. Researchers now hope that rewilding projects can take a more natural and hands-off approach — and that jays can shed some of their bad rep.

The two fields, which researchers have dubbed the New Wilderness and the Old Wilderness, had been abandoned in 1996 and 1961 respectively. The former was a barley field, while the latter was grassland — both were adjacent to ancient woodland. Researchers had suspected that the fields would gradually return to wilderness, but it was impressive to see just how quickly this happened, and how much of it was owed to birds.

Using aerial data, the researchers monitored the two sites. After just 24 years, the New Wilderness had grown into a young, healthy wood with 132 live trees per hectare, over half of which (57%) were oaks. Meanwhile, the Old Wilderness resembled a mature woodland after 39 years, with 390 trees per hectare.

“This native woodland restoration was approaching the structure (but not the species composition) of long-established woodlands within six decades,” the researchers explain in the study.

Part of this reforestation was done by wind, and researchers suspect that previous ground disturbance may have aided the woodland establishment — which is good news, as it would suggest that agricultural areas may be reforested faster than anticipated. However, animals — and in particular Eurasian jays, thrushes, wood mice, and squirrels — were also essential in helping the forests take shape. This handful of species provided much of the natural regeneration needed for the forest to develop. Jays, in particular, seem to have done a lot of heavy lifting.

Eurasian Jay (Garrulus glandarius). Image credits: Luc Viatour.

But just because land can rewild itself in time doesn't mean that a bit of help wouldn't make the process faster.  In my own experience, planting a copse on bare land where the topsoil had been removed,  spreading grass clippings on the subsoil transformed the soil, with grass (which stops the soil drying out and washing away) covering the bare earth in 2 seasons.

We will need to plant billions of trees to soak up CO2.  This story suggests that that nature will help us if she is given a chance.  Plus....hooray for jays.