Providing practical information to help you protect your farm from biosecurity risks

Go clean, not green

May 5, 2011

During December, January and February , floods inundated a large percentage of Queensland’s cropping regions, with some areas going under water more than once.

As the extensive clean up continues, it is timely to consider a few biosecurity issues to take into account during the recovery process and in planning for your next crops. From a biosecurity point of view, there are a number of potential threats that the movement of significant volumes of flood water can bring about. Although it may initially seem a lot of trouble to take some of these actions, they could save you a lot more trouble and cost in the long run.

To begin, the movement of flood water across paddocks will have brought with it debris and trash from adjacent paddocks, farms or even from outside the district. This trash could have any number of foreign weed seeds, fungal diseases or pests, and therefore any areas which have had flood trash pass through them or deposited on them should be monitored carefully, both before planting and during the growth of the crop. Naturally any weeds or diseases which emerge should be dealt with as quickly as possible.

When considering which crop to plant where, past rotational practices may not be effective, as the flooding of 2010 ‘diseased’ crops can spread disease to infecting adjacent paddocks.

For example, it is normally considered that having 500 metres between a past crop infected with ascochyta and the next crop is adequate. However if floods have crossed the paddock, diseased stubble may have moved from an infected paddock into a formerly ‘clean’ paddock with the trash. Thus it will be important to consider water flow and trash in deciding what crops to sow where in 2011.

Weeds are always a problem after floods. It is important to remember that not only will weeds be brought in on flood water and trash but may also be introduced with fodder drops to stranded stock. You may even find problems from drought feeding which only emerge now that there is excess soil water.

For some producers there will be a need to employ contractors to fix waterways, flooded fences or just to keep up with the extra work load. It is important to ensure that any vehicles or equipment brought onto your farm have been cleaned down. Also, remember to keep a record of where contractors have come from.

Here are five key activities to consider in the flood recovery process:

  1. Take notes about where water has run and or lain across your property and any trash it has left deposited. This is so you can keep an eye on these areas in the future.
  2. Go Clean, Not Green! Eliminate the greenbridge by spraying any weeds or volunteer seedlings as soon as possible and well before sowing the next crop.
  3. Keep an eye out for weeds in any areas where there have been fodder drops for either flood or drought affected stock, or water and trash.
  4. Make sure any vehicle or equipment coming onto your property is cleaned down before entering the property.
  5. Keep records of contractors that come onto your property to repair any damage or undertake recovery work.