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Qld. land clearing controls

To: "Andy Burton's Bush Tours" <>, Birding-Aus Mail <>
Subject: Qld. land clearing controls
From: (Richard Johnson)
Date: Fri, 25 Aug 2000 13:16:25 +1000
Andy, you're spot on as far as the mulga lands of Qld go. I have been prevaricating about replying to Peter et al. and you've saved me the trouble. However, I think I will say something now!
The degradation of land there is a fairly complex story with it's roots essentially in over-expectation of the capacity of a drought-prone area with low-nutrient, fragile soils and native pasture with limited resilience. (Over)grazing combined with removal of fire as a control on woody plants has freed several Eremophila spp and mulga to become dominant plants in what was generally a more open grassy woodland ecosystem. Invasion by these species ultimately produces a mid-dense shrub layer that effectively suppresses grass and leads to a bare soil surface even more prone to erosion. A hard subsoil crust is then left, reducing rainwater infiltration and so increasing runoff, and hence erosion so that a downward spiral in land degradation sets in.
So much for the lessons of hindsight. Today's graziers in this area are now in the situation where low returns per hectare mean that land remediation is simply not economically feasible. Sheep are the mainstay of the grazing industry ( the mulga is generally fairly ordinary cattle country as far as carrying capacity and fattening potential go) but note the poor state of the wool industry at the moment.  I have heard academics voice the opinion that even as a national issue, repair of much of the mulglands is just not on - there are too many other competing priorities.
So what are the graziers to do? Much land covered by 'turkey bushes' (E. gilesii, E. bowmanii) is pretty much gone, though E. gilesii is at times killed in large areas by grasshoppers. Dense mulga, on the other hand, can be 'pulled' or 'pushed' to allow regeneration of grassy understorey and this is what I think Julie McLaren is referring to. Remember, the only other option to this is to either push the remaining good country even harder - a short-term going-nowhere solution - or to get out. Who'd be a woolgrower in the mulga?
There are some bright spots on the horizon though. The wool price is picking up a bit and China might be buying big soon. A Landcare group in the Charleville has come up with a relatively cheap way of regenerating grass under turkey bush which might prove generally useful. And perhaps most important of all, most graziers are well aware of the limitations of their land and try to manage it accordingly. Before bagging the cocky, put yourselves in his/her shoes. how many of us can confidently say we always do the rational, sensible thing when it comes to resource use? And how many of us would be prepared to go under economically doing the 'right thing'?

Richard

Andy Burton's Bush Tours wrote:

I suspect that clearing to stop erosion just might make sense under
certain circumstances. Much of Australia's grassland has been
replaced by 'woody weed' under which there is little understorey
leaving the topsoils exposed to water runoff/flood.

Perhaps returning these lands to their original (Mitchell) grass
vegetation provides better ground cover and therefore more protection
for the topsoil

Any comment?

Andy

>Peter
>
>I was just beginning to think the same! Clearing to stop erosion????  It
>must be a solution endemic to Queensland as it would never work in
>Victoria around Bacchus Marsh or Lexton.  It sounds like on of those
>arguments against daylight saving a few years ago - that the extra hour
>of sunlight would fade the curtains quicker!!
>
>We ( you as a resident and I as resident "by birth and heart") must be
>missing something!??!  If anyone wants to prove me wrong and pay for the
>opportunity, then I will happily oblige.
>
>John Harris
>B.App.Sc.(Biological Resource Management and Biology), Grad.Dip.Ed
>Brisbane
>
>Birding-Aus is on the Web at
>www.shc.melb.catholic.edu.au/home/birding/index.html
>To unsubscribe from this mailing list, send the message
>"unsubscribe birding-aus" (no quotes, no Subject line)
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Cammeray,
NSW  2062
Australia

Ph 61 2 9954 0893

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+----------------------------------------+
Richard Johnson
Roma District
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