Simple changes have a big environmental impact

Winter feed crops play an important part in Simon O’Meara’s farm system, but the West Otago sheep and beef farmer has been adjusting his management to minimise their environmental impact.
Tuesday, 11 June 2019

Simon farms 565ha of rolling country at Wilden behind Heriot, running 3000 ewes, 800 hoggets and around 250 cattle.

Like many sheep and beef farmers in his area, between 5–10 % of his farm is in winter feeds crops which for Simon, are a mix of kale, swedes and fodder beet.

As part of his involvement in the Pomahaka Water Care Group, Simon has been made aware of the main contributors to water quality issues in the Pomohaka catchment and has taken steps to minimise sediment and phosphate losses – as a result of soil movement – from his farm over winter.

Simon says this process starts at crop establishment by selecting paddocks to suit the stock class. Dry, rocky paddocks are suitable for winter feed crops that will be grazed by cattle, while sheep can be wintered on heavier soils.

“The heavier the stock class the drier the paddock.”

He has also identified parts of his farm that he no longer considers suitable for winter feed crops. Pastures on these areas will be renewed in a straight grass-to-grass rotation, minimizing soil disturbance and sediment and phosphate losses.

When establishing a winter feed crop (spraying, cultivating and drilling), he, or his contractor, will identify where the Critical Source Areas (CSA) are. These include hollows, swales or any wet areas in the paddock and these are left in grass, fenced off and grazed last, after the crop has been eaten.

In winter, he begins grazing the crop from the top of the paddock so any soil and water flowing downhill is filtered through the crop.

Where hollows at the bottom of paddocks feed directly into waterways, he will build a bund or sediment trap that can be cleaned out over summer.

Simon has taken on-board the findings of P21 Project trial work at Telford Research Farm that showed that the protection of CSAs and strategic grazing management can reduce soil and P losses by 80-90%.

For Simon, this also means he will remove cattle from feed crops in particularly bad weather and run them on a dry pasture paddock but he will also back-fence strategically to stop cattle pugging the grazed areas.

With an increasing awareness of the environmental damage that can be caused by poorly managed winter feed crops, Simon says it is about having a change of mindset.

“We are used to having our paddocks look like golf courses but we have to get away from that.”

This might mean having long rank grass around CSAs and while this may not be not so aesthetically pleasing, the result will be better quality water for the whole catchment.