Integration of herb pastures into farming systems in New Zealand

The perennial herb pasture species chicory (Cichorium intybus) and plantain (Plantago lanceolata) are now widely in temperate pasture regions around the world. When combined with pasture legumes red clover (Trifolium pratense) and white clover (T. repens) both herb species enable livestock growth rates of sheep and bulls from late spring to autumn that are superior to those for livestock on perennial ryegrass (Lolium perenne) and white clover pasture. This paper provides data for a variety of livestock systems based on herb pastures plus some examples of how farmers are using these pastures

The growth response of Pasture Brome (Bromus valdivianus Phil.) to defoliation frequency under two soil water restriction levels

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Effects of Sheep Grazing Systems on Water Quality with a Focus on Nitrate Leaching

This article reviews the literature on nitrate leaching under sheep grazing systems and focuses on identifying future research needs. Urinary nitrogen (N) is an important source of the nitrate leached from pastoral agriculture. Urinary N excretion can be measured or simulated using models and has been well characterised for dairy systems. It is difficult to continuously monitor the urinary N excretion of sheep under field conditions; consequently, measurements of N excretion in sheep urine are limited. Urination events by sheep vary greatly in volume (0.5 L to 6.9 L), concentration (3 to 13.7 g N/L), and frequency (8 to 23 events/day); this variation results in a corresponding variation in N loading rates in urine patches. The amount of nitrate leached under pastures grazed by sheep has typically varied between 1 and 50 kg N/ha/year, but rates as high as 300 kg N/ha/year have been reported. The quantity of nitrate leached under sheep depends on the season, climate, quantity and timing of drainage, the interaction between forage production and stocking rate, fertiliser applied, N fixation by legumes, forage type, and grazing management. The majority of studies examining nitrate leaching under sheep grazing systems are more than 20 years old; so, there is little recent information on nitrate leaching under modern pasture-based sheep production systems. Further research is required to quantify nitrate leaching levels under current sheep farming practices, to understand the impacts of this leaching on water quality, and to help identify effective strategies to reduce the transfer of N from grazed paddocks to receiving water bodies. This additional information will help provide information for decision support tools, including models and management practices, to help sheep farmers minimise their impact on the aquatic environment

Effects of Sheep Grazing Systems on Water Quality with a Focus on Nitrate Leaching

This article reviews the literature on nitrate leaching under sheep grazing systems and focuses on identifying future research needs. Urinary nitrogen (N) is an important source of the nitrate leached from pastoral agriculture. Urinary N excretion can be measured or simulated using models and has been well characterised for dairy systems. It is difficult to continuously monitor the urinary N excretion of sheep under field conditions; consequently, measurements of N excretion in sheep urine are limited. Urination events by sheep vary greatly in volume (0.5 L to 6.9 L), concentration (3 to 13.7 g N/L), and frequency (8 to 23 events/day); this variation results in a corresponding variation in N loading rates in urine patches. The amount of nitrate leached under pastures grazed by sheep has typically varied between 1 and 50 kg N/ha/year, but rates as high as 300 kg N/ha/year have been reported. The quantity of nitrate leached under sheep depends on the season, climate, quantity and timing of drainage, the interaction between forage production and stocking rate, fertiliser applied, N fixation by legumes, forage type, and grazing management. The majority of studies examining nitrate leaching under sheep grazing systems are more than 20 years old; so, there is little recent information on nitrate leaching under modern pasture-based sheep production systems. Further research is required to quantify nitrate leaching levels under current sheep farming practices, to understand the impacts of this leaching on water quality, and to help identify effective strategies to reduce the transfer of N from grazed paddocks to receiving water bodies. This additional information will help provide information for decision support tools, including models and management practices, to help sheep farmers minimise their impact on the aquatic environment

Will current rotational grazing management recommendations suit future intensive pastoral systems

This review aimed to determine whether current grazing management practices will suit future intensive rotationally grazed pastoral systems. A review of literature on grazing management recommendations found that there was good agreement on the ‘principles’ required for optimal grazing management. While these management practices have stood the test of time, it is concluded that shifts in external pressures (e.g., climate, plant selection and breeding, system intensification) compared to the period when farm-level grazing recommendations were first developed, may necessitate a rethink of current grazing recommendations. Examples include greater pasture masses (e.g., around 4000 kg dry matter (DM)/ha vs. the recommended range of 2600 to 3200 kg DM/ha) where short-rotation (annual, biennial) and tetraploid ryegrasses are sown, provided a consistent post-grazing residual can be maintained (possibly between 40- and 70- mm height). Milder winters and the use of ryegrass cultivars with higher growth rates in late winter/early spring may necessitate either lower target pasture covers at calving or shorter rotation lengths during winter. Longer grazing rotations (well beyond the 3-leaf stage, i.e., equivalent to deferred grazing) can be recommended for select paddocks from mid-spring into summer, to increase seasonal resilience across the farm. Longer residuals (even up to 70 mm - i.e., almost double the recommended height) might improve plant survival during periods of high stress (e.g., heatwaves, droughts). Lastly, diverse species pastures may require specific management to suit dominant species other than perennial ryegrass

The role of forage management in addressing challenges facing Australasian dairy farming

Forage management underpins the viability of pastoral dairy systems. This review investigated recent developments in forage research and their potential to enable pastoral dairy systems to meet the challenges that will be faced over the next 10 years. Grazing management, complementary forages, pasture diversity, fertiliser use, chemical restriction, irrigation management and pasture breeding are considered. None of these areas of research are looking to increase production directly through increased inputs, but, rather, they aim to lift maximum potential production, defend against production decline or improve the efficiency of the resource base and inputs. Technology approaches consistently focus on improving efficiency, while genetic improvement or the use of complementary forages and species diversity aim to lift production. These approaches do not require additional labour to implement, but many will require an increase in skill level. Only a few areas will help address animal welfare (e.g. the use of selected complementary forages and novel endophytes) and only complementary forages will help address increased competition from non-dairy alternatives, by positively influencing the properties of milk. Overall, the diversity of activity and potential effects will provide managers of pastoral dairy systems with the best tools to respond to the production and environmental challenges they face over the next 10 years