WASHING AWAY – PART ONE – DAM IT UP

Topsoil is that thin band of living matter that lies across the landscape.  Except when it is undermined or dissolved by rain and carried downhill into first the gullies, then the waterways, leaving the water silty and the landscape denuded.

As a child I loved to play among the eroding soil spires where you could imagine yourself in a miniature Grand Canyon.  My little brother Andrew made endless tracks for his Matchbox cars in the walls of the gully near the house we now call Wombat Hollow.  Occasionally he and I would help the erosion along by creating bucket-powered rivers and flood catastrophes that would flush the tiny battered vehicles over cliffs and down to their doom.

The traditional way to discourage gully erosion is to throw in some old car tyres, kitchen equipment, broken fences and spare car bodies, and hope they will collect silt.  This sometimes even works.

Mum was very cross when Dad chucked some of the old horse-drawn farm machinery into a gully.  ” I wanted to put that in the garden” she protested.

“They’re all still  there,”  was Dad’s reply.  ” You just have to dig them out of ten feet of silt.”

So they’re still underground waiting for a confused archaeologist.

Other dumps were less successful, leaving exposed piles of wire, roofing tin and old fridges sitting out on the hillsides.

In some places I’ve been able to make use of the piles.  Trent, my excellent planting assistant, was happy to have the wrecked mini-Moke from near the woolshed.  Some of the corrugated iron sheets went to repair the storeshed roof.   The big set of gates have made a handsome addition to the hayshed.

Then I found an extra dumping area behind the hayshed.  Surprise. The dump contents were mostly hopelessly tangled in barbed wire, the rest covered with just enough dirt to make it awkward to extract anything useful, so I’m slowly getting the whole pile compressed and covered up with dirt using a bulldozer.  Then I can re-establish a good grass cover over the top.

Suddenly this little valley has a much better shape.  To establish grass cover, when the topsoil has been spread, I’ll add a couple of bales of local hay, plus some mushroom compost and throw in some native grass seed.

Above the new earthen dam is an existing dam which I’m also going to work on this year.  The silt was dug out of it three years ago, but is back again, because the area above it is bare.  There’s little shelter in the small paddock above it, so the sheep like to snuggle down in the low ground out of the wind, leaving it worn down and easy to erode.

I plan to reinstate the fence between the two paddocks.  Originally, separate mobs of sheep could get water from each side, but that fence has been teetering for quite a while.  I also have a grant to make a plantation on the rocky knoll to one side of the dam, including planting 100 drooping sheoaks (allocasuarina verticillata)  for glossy black cockatoo food (Greening Australia), and 150-200  mixed trees and shrubs for shade and shelter (Landcare 25th Anniversary Grant).

I’m hoping to also protect a big part of the dam edge and plant it with riparian plants like lomandra (mat rush) that may help keep the water cleaner.  The sheep will still have access on one side.

One day it might even look slightly like Sue McIntyre’s erosion controlling dam at Gang Gang. Last Sunday we had a walk and afternoon tea there with Murrumbateman Landcare.   It was great to see what is possible with a native grassland.  Lovely.