Early action helps farm weather dry

But what do you do when it’s too dry even for kikuyu? That question is being asked in Northland now as the region faces its third drought in four summers and ground water levels are now so low that dams are drying up.

The management team at the Northland Agricultural Research Farm is putting its money on planning and playing the ‘long game’ and regional science manager Kate Wynn says it is paying off.

About 245 cows are being milked on an 84ha milking platform – down from 270 cows normally. The property is split into two farmlets researching the effectiveness of mulched kikuyu pastures versus rye grass pastures in Northland conditions.

However, with rain not falling on the property for two months – in contrast to 173ml and 337ml falling in the same periods in 2012 and 2011 respectively – not much pasture, if any, will grow.

Wynn says 115 cows are currently being milked twice a day on the 40ha rye grass farmlet, and 130 cows on the 44 ha kikuyu farmlet. Wynn says cows on the kikuyu farmlet were losing condition faster and producing less (MS/cow 0.9 cf 1.2) so the decision was made to go OAD in this herd sooner. “Mid-February was our trigger point to stop worrying about production for this season and start looking ahead to making sure the cows are in good condition for next season.”

The property has produced 1000kgMS/ha over the last three years despite having to deal with the last big drought in 2010 and produced 99,000kgMS in the 2011-12 season.

The farm also achieved submission rates of 97% within five weeks this season getting a non-return rate of 74% at the end of AI. Wynn attributes this to care taken of individual cows at this time of the year.

Any cows with a body condition score under 3.5 went on to OAD milking from early January; any cows producing less than 0.6kgMS were dried off from the end of February, says Wynn. “This is mainly the heifers and second calvers. This is policy even if it not a drought.”

While a high somatic cell count can be an indication that it is time a cow is dried off, Wynn says cows with a somatic cell count of up to 600 can be milked so long as there are enough cows being milked into the vat to dilute the total bulk milk SCC; but somatic cell count and body condition score are taken into account individually. “All figures are based on an individual cow basis not on the herd average.”

Dry conditions have taken their toll on pasture covers as well. Wynn says it isn’t as dramatic for kikuyu but can be incredibly damaging for ryegrass pastures. “It takes longer for the plant to recover and some plants will die, leaving bare patches and areas for weeds to hang out.”

Farmers with facilities to stand stock off can avoid this by allowing animals to graze down to pasture covers of about 1500kgDM/ha but admits this is not always possible. The research farm limits this by providing supplements to animals on the ryegrass property, says Wynn.

In fact Wynn says stock on ryegrass get markedly more supplement than those on kikuyu. Cows on ryegrass get 5kgDM of PKE and 3kg of turnips a day on top of the 2-3kgDM of rye pasture still available to them.

The herd on the kikuyu pastures get 6-8kgDM of PKE a day with 3-4kgDM kikuyu pasture still being available.

PKE is fed out in two lots: the first on the stand-off pad before morning milking and the remainder in trailers in the paddock. The ryegrass herd goes onto turnips following the morning milking.

Wynn says the challenge will be making sure there’s enough supplement stored away for the two weeks after droughts break. “Pasture will rot during this period and you need to give it a chance to recover.”

Wynn also says it is important that young stock don’t get forgotten during this period and actually get some form of supplement.