Limestone Downs Dairy Conversion

In late July 2013 one of Waikato’s largest drystock properties, the C Alma Baker Trust’s Limestone Downs, converted 20% of its farm to dairying. The property has a history of pioneering and innovation. Last year the management team on the 2500ha effective coastal property launched into the development of a pioneering dairy farming unit on farmland south of Port Waikato.

Five hundred mixed-age cows and 200 first-calving heifers have been resident on the 425ha dairy platform since early June, bought from all around Waikato.

While Alf Harwood and farm supervisor Kevin Lowe admit is not perfect dairy country, the history of the past 20 years tells them one kilogram of dry matter eaten by dairy cows is worth twice as much as a kilogram eaten by either sheep or beef cattle.

Starting a dairy farm from scratch is never for the faint hearted and Limestone Downs Trust and its association with Massey University meant the farm is in the public eye, so the farm leadership team were determined to get it right.

There is a new 60 bail rotary for the 700 cows they’re milking. Out in the yard is Protrack EID reading and an automatic drafting system. A 100 metre long feed pad was built and there’s also a state of the art effluent system incorporating weeping walls with 200 days of storage. Many kilometres of riparian waterway protection, power reticulation, re-contouring and drainage channeling was undertaken, which has kept earthworks contractors busy for 18 months.

About 120ha of peaty flats along the north bank of the Kaawa stream were humped and hollowed, drained and then re-sown and re-fenced.

Limestone’s team decided to undertake a big re-grassing project for the new dairy – there was a major autumn sowing of perennial ryegrass. These grasses were sown without clover to facilitate weed spraying. And later sown with white clover. New paddocks were grazed with sheep to encourage tillering – before the cows arrived. Soil tests were done for all the paddocks after humping and hollowing. Olsen P levels were low, as was soil pH. The property has a big application of lime along with 500kg/ha of super.

Local iwi were included in the consultation process and an ecologist was engaged to carry out an environmental monitoring programme at Limestone Downs, to give the management team a clear picture of the before and after effects of the dairy conversion. Monitoring will be focused on freshwater ecosystems. Ecologist Gary Kessels says “cultural indicators” are closely aligned with environmental markers such as water clarity, the presence of scum or foam, fish schools, riverbank vegetation and native species.

Three streams are being sampled, one a control outside the dairying area, another alongside the dairying area and one within it. Water quality will also be sampled during four storm events over three winters, as this is when the bulk of nutrient transport takes place.