Learning winter’s lessons

Farmers whose operations have been negatively affected by this year’s winter weather are being urged to apply the lessons learned next winter to help protect profits and the environment.

"The way farmers manage their stock in winter can have a significant impact on things like pasture quality, sediment and nutrient run-off to waterways," said Environment Waikato’s catchment services committee chairman Andra Neeley.

"Anyone’s who’s had problems this winter should look to apply the lessons learnt next winter to help protect the profitability of their farm and the environment."

Heavy grazing of wet pasture, and the resulting compaction of soil by stock, can reduce pasture growth and impact negatively on farm productivity.

Recent research reports showed that pastures lose between 30 per cent and 60 per cent of potential growth in the three to nine months after just one severe treading event when soils are wet, said EW sustainable agriculture coordinator Bala Tikkisetty.

He said soil aeration, preferably during spring, was a way of overcoming the damaging effects of compaction on soil.

It was very important to consider the soil conditions at the time of aeration or cultivation.

"One test to assess if soils are suitable for primary cultivation is taking a piece of soil about half the volume of your index finger.

"Try to make a ‘worm’ by rolling the soil on the palm of one hand with the fingers of the other until it is about 50 mm long and 4 mm thick, using 15 to 20 complete forward and back movements of the fingers. Conditions are suitable for cultivation if the soil cracks before the worm is made. The soil is too wet to cultivate if you can make the worm."

Mr Tikkisetty said winter-feed paddocks can present special difficulties when it comes to cultivation as the top few centimetres of soil can be "puddled" by stock in wet conditions and be prone to wind erosion once it has dried out. "This is because this top layer of soil has lost all its structure and can lift from the paddock very easily. Turning this type of ground over as soon as soil conditions permit in the early spring will minimise the risk of losing this fine layer to the north-westerly wind."

Also, compaction of soils, combined with higher livestock densities during the winter, can cause a localised accumulation of stock effluent which is then more easily transported to surface water.

"These wintering problems with effluent underline it’s a good idea not to give out supplementary feeds in areas where run-off water may reach any water body. If possible avoid feeding out in these paddocks altogether," said Mr Tikkisetty.

Feed pads and stand-off pads are options for protecting soil physical structure over wet periods, he said.

"When building your pad allow for solid and liquid waste disposal. Design the pad in such a way that the contaminants run into your effluent disposal system for the dairy shed. Locate the feed pad or stand-off pad well away from any waterway."

For further information, contact Bala Tikkisetty on 0800 800 401.