(3) machinery selection (with emphasis on minimisation)
FARM LAYOUTInitial farm design is a compromise between the ultimate square block with even length rows , and the capital costs of achieving that ideal layout. The particular compromise a farmer will choose will depend on three major considerations -
(1) The availability of start-up capital.
(2) The INTEREST costs of borrowed capital over the anticipated repayment period.
(3) The anticipated ultimate size of the farm.
The features to aim for in the optimum farm layout will include-
While this goal is desirable, it is seldom achieved on the extremely variable soil types found on the Burdekin - Haughton flood plain. It is in this area of farm design that there are two very distinct and different trains of thought. One believes that farm layout should be designed around the goal of even soil types within the one drill. It is acknowledged that this is most desirable, but when attempting to achieve it results in widely varying drill lengths and drills at an acute angle to the headland, I lean more to designing around topography and rely on using earthmoving machinery to shift soil where necessary to achieve acceptable soil consistency. Soil swapping to achieve consistency is expensive but does not have to be performed at the initial development stage. This "fine tuning" of your farming operation can be done after the first or even second crop cycles and paid for with profits rather than increased borrowings in your initial start-up years. With regard to farm layout, I favour designing to achieve optimum efficiency for the very long term. Anything less, in a rapidly advancing technological world will most certainly cause us to face competitive cost pressures from other current and possibly completely new world sugar producers sooner than we may have needed to.
(4) TAILWATER RETURN SYSTEM FOR IRRIGATION RUNOFF
This is an absolutely essential part of any large scale irrigated canefarming operation.
While this system does reduce the normal loss of water that flows out the end of each drill while irrigating, the major benefit is the flexibility it allows in the management of irrigation. No longer do farmers have to spend many hours each day counting drills, turning a few on, closing a few off throughout the day. With a tailwater return system in place, drills 800 -1,000 metre long are ideally irrigated on a 24 hour change interval.
Enough drills are operated in one setting, so as to achieve the irrigation water reaching the end in 20 -22 hours with an extra 2 hours allowing for a more even infiltration on the lower end of the drills and also to ensure that the slowest drills do reach the end. With the trend to longer drills, one of the undesirable consequences has been the increased variation in times required for irrigation water to reach the end. A tailwater return system eliminates the loss of resultant runoff without the need for monitoring and adjustment of drills on an individual basis.
FARM PRACTICES PLANTING
(1) Soil is ripped using parabolic shaped tynes in November - December preceding the wet season.
(2) Heavy application of ROUNDUP (6L/ha) during fallow to eliminate problem weeds (eg paragrass, passionfruit vine, nutgrass).
(3) MARCH - APRIL, weather permitting, soil is prepared conventionally using a combination of offset disc, and Yoemans chisel plough. No cross working is performed as that requires too much land to be prepared ahead of the planters.
(4) Planting is carried out by contractors using trash planters. The shape of the furrow
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MUST be a VEE, with soil cover following irrigation aimed to be between 35 - 55mm.
Drill spacing is 1.6m (5'3").
Various forms of ridge planting are emerging and will in time become accepted practice on large scale farming operations. Rougher than optimum and more variable ground conditions may limit this planting technique on newly developed land.
(5) Grass and week control is done using a combination of pre and post emergents applied immediately following the second irrigation. (GESAPAX COMBI + 24D + DIUGRANZ). This is applied by aircraft.
(6) No cultivation until the cane is big enough for the centres to be knocked down and hilled up. Fertilizer is applied conventionally beside the stool.
(7) Irrigation should then be scheduled using an evaporative pan. Advice on how to implement an irrigation scheduling system is readily available from your local BSES officer.
There are two excellent publications I would strongly recommend every farmer growing cane in the BRIA should read. They are comprehensive, yet easy to read and are most helpful in gaining the necessary understanding of soils and water qualities to manage an
efficient irrigation program. They are -
• Understanding and Managing Burdekin Soils by QDPI.
• Irrigation of Sugarcane by BSES and SRDC.
RATOONING
(1) Following harvest, ratoons are irrigated as soon as possible.
(2) When the field has dried out sufficiently, fertilizer is applied deep 140 - 180mm (514" - T) into the centre of the stool It is important in a furrow irrigated situation, to ensure the fertilizer placement is below the level of water in the irrigation furrow to ensure that
subsequent water movement through the "hill" does not bring fertilizer to the surface.
This is in contrast with acceptable practice in raingrown, or overhead irrigation areas. No problems have been observed with application rates up to 250kg/ha of N and 70kg/ha of
Advantages of stool splitting fertilizer application:-
• Does not require cultivation of normally compacted interspace to ensure over fertilizer is covered with soil.
• Low horsepower requirement as the "hill" is generally soft and uncompacted, with a covering of loose soil left by the harvester,
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• Fertilizer is less accessible to grass and weeds.
• Eliminates losses from volatilization of fertilizer into the water while irrigating long rows of rubbly soil with fertilizer placed in the interspace.
• Stool splitting is environmentally friendly as it virtually eliminates fertilizer leaving the field and being carried into creeks and ultimately into the ocean.
Sodic duplex soils may require some cultivation to improve water infiltration in ratoons. Ripping of the centres together with the application of gypsum is generally required to achieve acceptable yields from these problem soil areas.
MACHINERY REQUIREMENTS
Machinery requirements can be minimised with good planning and management of the broadacre canefarm. The first task is to determine the farming practices you -will employ in growing the cane. Most farmers start off in the BRIA basically performing the same procedures they use on their home farm. Some of these will suit the conditions found on the new farm but many will not.
Once deciding on your preferred farming system, I find it very helpful to do a matrix of all the implements and tractors you anticipate requiring. The schedule on page 7 lists the Davco Farming machinery inventory for 1995. Once deciding on a particular farming system, there is little scope to reduce the range of implements needed, but there is significant scope to minimise the number of tractors required which are in effect the big cost items. In my matrix, I leave a column spare to use whenever I feel there may be a cost effective benefit of another tractor in the system.
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