Friday, 2 December 2016

Developing land from the air


Doug McKenzie has swapped life as a rural banker to return to the land. His family bought the two properties that now make up Patitapu Station at Alfredton in North Wairarapa, back in 2000 and 2003.

In 2007 he and wife Jo made the windswept 2,550ha farm, 20km east of Eketahuna, their home. Here they run 10,500 Romney cross ewes, 400 Hereford/Angus cross cattle, plus replacements and trading stock. They aim to finish up to 75% of the lambs on the property but this is dependent on the season and some years it can drop to 30%. The steers are sold at the weaning store, while heifers stay on the property and are killed at either 18 months or 2.5 years. It is a productive property but there is always room for improvement with the eight-year average lambing at 138%, and calving at 92%.

Large areas of the windswept land are covered in regenerating native bush and scrub blocks, leaving 1,760ha of effective land where Doug and his father have launched a significant development programme particularly focused on addressing the basics of soil fertility, revolving around the tried and true combination of P, pH, S and N.

The land is mixed terrain with 136ha flat or under cultivation with the balance mainly medium to steeper hill country. Doug and Jo are confronted with huge variability in physical resources including altitude, aspect, soil type, slope, and rainfall. Cropping consists of 40-60ha of red/white clover mix for lamb finishing, summer turnips and rape. The weed and pest influences come from gorse, manuka regeneration, thistles, porina and grass grub. Classed as semi summer safe, it can climatically go any way in any given season.

Integral to the development programme, is working with Aeroworks over the past two seasons as part of Ravensdown’s Primary Growth Partnership project on remote sensing and variable fertilizer application.

We’ve also been doing a lot of work with Massey and AgResearch, the other partners in the PGP programme. The property has been extensively tested and mapped via My Ravensdown and broken into productive blocks for differential applications. It’s been fascinating.

Doug says previously the farm had a very poor fertilising history and associated soil test results before the analysis highlighted this. Fertiliser, in conjunction with infrastructure development (fencing/water/yards) and hoof and tooth grazing management, have transformed the property. All are interlinked.

Doug has had a long association with Ravensdown, working with agri manager Greig McLeod since 2007.

“Through Ravensdown and Aeroworks’ technology advances and service model, we are increasingly targeting products and rates to specific areas at specific times to get the best physical and financial responses.”

Basic super + selenium prills have been used together with maintenance fertiliser, depending on stocking rates.

“We’re becoming more scientific on how those areas are set. The range varies from 200kg/ha to 350kg/ha depending on requirements. We have found the strategic use of urea in spring works well to get the whole system moving, plus some use of DAP with crops and when economic for spring applications.”