Water movement in soil - Soil Essentials: Managing Your Farm's Primary Asset - page 137

Responding to test results

Poor infiltration on normally good soils
A soil that used to drain well but now has waterlogging problems indicates a loss of
crumb structure, or the formation of hardpans. These problems may be due to
excessive cultivation, over cropping or compaction by stock. It may also be caused
by problems higher up the slope draining more water onto the soil being
considered.

If cropping, options may include:

Deep ripping to break up hardpans.
Changing to minimum till or direct drilling methods of sowing.
Deep ripping and sowing down to deep-rooted perennial pasture.
Avoiding trafficking the soil with machinery as much as possible, especially when
the soil is very wet. Wide tyres with low inf lation pressures significantly reduce
soil compaction if machinery must be used on wet paddocks (Figure 44).

If livestock are contributing to the problem, options may include:
Try to have as few livestock as possible on high-risk paddocks when the soil is wet.
Practise rotational grazing so livestock are only on a paddock for say one week in
seven. This gives the soil a chance to self repair.
Sow deep-rooted perennial pastures if the climate and soil allows.
Aerating the soil using a narrow tyned ripper to loosen the soil and break up
hardpans as they develop may be warranted.
Use a management system that encourages high levels of organic matter and
biological activity in the soil.

Figure 44 A machine suitable for breaking up shallow hardpans. ( Soil Sense P-04)