Good pasture system pays off for months

22:03, Nov 21 2012

Spring management of pasture is critical because it affects the rest of the season, according to a pasture expert.

The management of surplus growth in late spring stopped the development of rank pasture which lost density and clover, New Zealand Agriseeds representative Andrew Bendall told about 50 farmers at Beef + Lamb New Zealand's Taranaki beef focus day at Tariki last week.

What was done in spring affected the growth of dry matter the following autumn and pasture covers at the start of winter.

"Spring management is critical," he said. "I cannot emphasise that enough. It's very hard to get right - it's a continuous juggling act. It sets you up for the whole season because it has a flow-on effect.

"Otherwise, you're on the back foot with poor quality pasture which takes the weight off your stock."

Bendall said November and December were "as good as it's going to get" for pasture growth, but farmers tended to think the rate and quality apparent now would continue through the season.


"So how do we keep pasture quality for cost-effective summer forages?"

Liveweight gain in stock was relative to the energy value of the diet and animals needed more than 9 megajoules per kilogram of dry matter (MJ/kg DM) to grow.

If feed was not well-managed, stock would not gain weight. After three days in one paddock, stock were likely to gain no weight because the pasture would be eaten out.

There were five ways to control spring surpluses:

Making high-quality silage with high metabolisable energy (ME) after shutting paddocks before the surplus was apparent.

Taking paddocks out for summer crops or pasture renewal meant there was less grass to worry about.

Grazing beef cattle with ewes and lambs kept spring pasture in check.

Retiring selected paddocks on sheep farms from grazing allowed good control over the remainder. Steep paddocks should not be retired.

Sowing late-heading ryegrass as part of a pasture renewal plan.

Bendall said managing summer pasture quality also required monitoring of post-grazing residuals and use of nitrogen.

"Residuals will determine the quality. The quality today is only as good as you left it 21 days ago."

Small amounts of nitrogen - 25-20kg/ha - could be used strategically to boost growth and encourage tillering.

Farmers considering a summer crop should focus on cost- effectiveness and yield. "You only get that if the pre-work is done. You need high utilisation and to have a plan. Why are we putting in a crop and when do we want it?"

A rape crop sown during a spring surplus provided quality summer and autumn feed. The addition of clover to chicory and plantain added substance in summer. Hybrid grasses with short, leafy clover provided high ME because they were high in sugar, critical for weight gain. Good ryegrass had higher ME in winter than summer.

"If you focus on quality pasture, the stock will eat more because it's more digestible," he said.

Farmers had been spoilt by a system that allowed them to produce what the season dictated and which they then expected to be marketed.

"But they need to be producing what suits the consumer," he said.

Taranaki Daily News