Pasture management refers to the planned establishment, use, and renewal of pasture to maximise feed supply, pasture persistence, and animal performance while protecting soil and plant health. Good pasture management in New Zealand’s grazing systems means growing the right pasture species in the right place, and grazing them at the right time and intensity so that pasture regrows quickly and maintains high nutritional value. This relies on understanding pasture dry matter (DM), measured as kg DM/ha, which is used to quantify feed supply, intake, and demand across the farm.
Most New Zealand dairy pastures are based on perennial ryegrass and white clover, with cultivars selected for yield, persistence, seasonal growth pattern, and tolerance to pests and grazing. Establishment and renewal (regrassing) involve planting these species into suitable paddocks at appropriate times of year and allowing new pastures to establish before grazing, to support long-term pasture persistence and utilisation.
Pasture cover refers to the quantity of grazeable pasture present across a farm at a given time, expressed as kilograms of dry matter per hectare (kg DM/ha). It is a core measure used to inform feed allocation decisions and support animal performance, particularly during periods of high feed demand such as spring.
Once established, pasture is managed through grazing rotations or rounds, which determine how long cows graze a paddock and how long it rests before being grazed again. Rotation length is adjusted to match pasture growth rate (kg DM/ha/day) with herd feed demand. A key seasonal concept guiding these decisions is the balance date, the point in spring when daily pasture growth equals herd demand. Before balance date, rotations are lengthened to protect pasture cover and maintain the farm’s average pasture cover (APC) when growth is limited; after balance date, rotations are shortened to manage surpluses, maintain quality, and prevent pasture from becoming too long. Tools such as the feed wedge, which ranks paddocks by pre-grazing cover, are commonly used to plan grazing order and identify surpluses or deficits.
A key operational principle is leaving an appropriate post-grazing residual, the amount of leaf left behind after grazing, often linked to grazing at the optimal leaf stage of regrowth in ryegrass. Grazing too short (overgrazing) weakens plants, reduces pasture utilisation, slows regrowth, and can shift species composition toward less desirable species. Grazing too lightly (undergrazing) allows pasture to become too long and fibrous, lowering digestibility and protein content, increasing selective grazing and wastage, and slowing subsequent regrowth. Balancing pre-grazing cover, residuals, and rotation length is central to maintaining productive, high-quality pasture that underpins animal performance and profitability in pasture-based systems.
Because cows walk to the shed once or twice a day, the distance between paddocks and the milking shed has a major influence on their daily workload. In most New Zealand systems, cows cover a total of 2 to 7 km per day, which at an average walking speed of around 55 metres per minute (about 3.3 km per hour) equates to roughly 45 minutes to 2 hours of walking. Industry guidelines recommend keeping the farthest paddocks within about 2 km of the shed to limit fatigue, maintain lying time, and reduce the risk of lameness. Longer distances are possible on some farms, but they increase pressure on the feet and heighten vulnerability to lameness, especially when tracks are uneven or damaged, when cows are in early lactation, or when weather conditions make surfaces slippery.
When herd sizes become large, the effective milking area is often not sufficient to meet the herd’s feed requirements while still keeping all paddocks within the recommended 2 km walking distance of the shed. As a result, many farms rely on additional land outside the milking platform to support the system. These off-platform areas, commonly referred to as run-offs or support blocks, may be used for grazing young stock, wintering dry cows, or growing supplementary feed such as silage, maize, or other feed crops. Although these blocks do not form part of the milking platform itself, they play an important role in maintaining feed supply, managing pressure on pasture, and allowing the platform to focus primarily on supporting the lactating herd. Some of the additional feed produced may be stored in silage bunkers on the farm.
When the milking platform and support blocks cannot grow enough pasture or feed to meet the herd’s requirements, many farms bring in supplementary feed from outside the system. This may include purchased silage, hay, maize, grain, or by-product feeds such as palm kernel expeller, which help buffer cows through periods of low pasture growth or high nutritional demand. About 60% of These supplementary feeds are typically provided to cows on a feed pad, which is most commonly located just before or just after the milking shed. In 2022, New Zealand imported about 3.7 million tonnes of supplementary feed, with the dairy sector consuming around 75% of these imports, meaning that close to 60% of feed ingredients used nationally are now sourced from overseas.
In parallel with bought-in feed, some farms also make use of contract grazing arrangements, where young stock or dry cows are grazed on another farmer’s property for a fee. Contract grazing reduces pressure on the milking platform by freeing up pasture for the lactating herd and shifting some of the feed demand to external land.
The most common contract periods for heifer grazing are:
Some dairy herds will also arrange for winter grazing for their mixed-age cows. Both purchased feed and contract grazing introduce additional costs and logistical considerations including biosecurity risks from moving feed products and live animals across the farm boundaries.
To describe how farms differ in their reliance on supplementary feed, DairyNZ classifies New Zealand dairy systems into five broad farm system types based on the proportion of feed imported onto the milking platform.
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