Dealing with salinity in Wheatbelt Valleys - Department of Water

Lloyd
Table 3. Sheep grazing days in a 32 ha paddock grazed throughout 1999. The area was direct seeded to
saltbush in August 1997. It had not been grazed until the sheep were introduced in January 1999.
Date in Date out Total days Sheep numbers Sheep days
04/01/99 11/01/99 8 450 3,600
11/01/99 08/03/99 56 386 21,616
08/03/99 16/03/99 9 365 2,385
17/03/99 11/04/99 19 480 9,120
01/05/99 06/05/99 6 545 3,270
06/05/99 14/05/99 8 586 4,688
07/06/99 20/06/99 14 375 5,250
21/06/99 01/07/99 11 455 5,005
01/07/99 15/07/99 17 300 5,100
31/07/99 14/08/99 15 300 4,500
16/09/99 26/09/99 11 1,052 11,572
09/11/99 18/11/99 10 465 4,950
19/11/99 22/12/99 34 527 17,918
99,874 sheep days @ 32 ha @ 365 days per year = 8.6 DSE/ha (annualised basis)
It can be seen from the details from “Bundilla” that
saltbush, in conjunction with understory annuals
and hay, can significantly increase the carrying
capacity of saltland. It can also be seen that
saltbush can significantly lower watertables.
ECONOMICS – IS IT WORTH IT?
But what of the economics? Is it worth it? From
the work done on “Bundilla” and from the
experience of other saltland farmers, the answer is
undoubtedly "YES". In seasons of below-average
winter annual feed production, the addition of hay
enables sheep to be retained which otherwise
would have to be sold, agisted or fed expensive
supplements. All the saltbush is now direct seeded
on “Bundilla” with our own seeding machine.
Seed is harvested on the property.
– 6 –
Farmers’ costs can be reduced significantly if they
are prepared to do more of the work themselves.
For instance, the retail cost of saltbush seed is
around $50 per Kg, but we harvest our own. To
get a true cost of establishment all costs need to
be included. The actual cash cost for us to seed a
hectare of saltbush is the cost of the spray ($10)
and vermiculite ($14), a total of $24/ha. For this
we would expect up to 2,000 plants per Ha. So
much for it being too expensive. Where else could
we more than treble production from an area of
land with such a small additional cost?
Table 4 shows the relative cost of contractor
versus farmer operated direct seeding. If the row
spacings are increased with less rows of saltbush
per hectare, the costs for both contractor and
farmer-seeded will be reduced accordingly.