H1 (87) Ecology and Grazing Management AGRI20036 Clear and Concise notes

Description

These notes contain information on; Australia’s Pasture and Grassland resources - Pasture management system - Alternate perspective of pasture management system - What makes a productive pasture system? - Features of pastures - Australian Grasslands - Effective Rainfall - Land use by area – 2014/2015 - Summary of Australia’s grasslands - Classification of Grasslands and pastures - Pasture zones of Victoria - Introduced Pasture species - Native Pasture species - Grasses vs Legumes - Temperate pastures in Southern Australia - Unimproved, native species, Perennial, grass dominant - Unimproved, introduced species, annual, grass dominant - Improved, introduced, annual, Grass/legume - Improved, introduced, perennial, grass/legume - Pastures of Victoria; status and issues - Perennial pastures with good legume base are key tool for: - Pasture re-sowing in Victoria - Challenge for livestock producers Population biology of pasture plants - Plant population dynamics – equation - Define persistence - Define population biology - Annual species lifecycle - Plant population biology – annual plants - Flowering times of sub-clovers – 2 cultivars - Developmental morphology of the tiller – grasses - Phalaris vs Perennial ryegrass - Developmental morphology of the stolon - Developmental morphology of the crown - Plant population biology – perennial plants - Clonal growth - Plant population biology – perennial ryegrass - Plant population biology – tiller production - Perennial ryegrass survival pathways in summer-dry environments - Plant population biology – Phalaris survival - Pasture species and cultivars in Australia - Define cultivar - Origins of Australian pasture species - Role of plant breeding - Achievements of plant breeding – phalaris - Achievements of plant breeding – sub clover - Plant breeding methods - Ecotype selection - Polyploidy - How are species and cultivars used? - Main roles of pasture species – important principles - Grasses, legumes, forage herbs - Grasses - Main role of pasture species – grasses - Legumes - Main role of pasture species – legumes and forage herbs - Principles and practices in the selection and use of species and cultivars - Perennial ryegrass - Italian ryegrass - Hybrid, short-lived ryegrass – Lolium X boucheanum - Phalaris - Cocksfoot - Tall fescue - Prairie grass - Important native grasses - Subterranean clover - White clover - Strawberry clover - Red clover - Balansa clover - Lucerne - Medics - Forage herb - Which cultivar is best? Pasture Growth - Growth and photosynthesis - Pasture growth - Pasture regrowth curve - Pasture regrowth – ceiling yield - Pasture regrowth curve and average growth rate - Mass flow and tissue turnover – plant level - Tissue turnover during regrowth - Key management factors to control with grazing management - Pasture yields – how fast/ much can pastures grow - Seasonality of pasture growth - Climate change and pasture growth patterns Pasture Improvement - What is meant by “Pasture improvement”? - Degraded pasture vs. improved pasture - Dry sheep equivalent (DSE) - Stocking rate - Effective grazing area - Carrying capacity - Matching seasonal pasture growth curves with livestock production - Grime’s major selection forces on plant communities - Competition-stress-disturbance (C-S-D) model of plant strategies - Aim of pasture improvement and the C-S-D model - Characteristics of plant competitors - Characteristics of plant stress-tolerators - Characteristics of plant disturbance tolerators - Relationship between soil fertility and pasture production - Measures of soil nutrient status - Principles to practice - Grass-legume interactions and the role of legumes - Managing the nitrogen cycle and grass-legume dynamics - Benefits of pasture improvement - When are benefits from pasture improvement greatest? - The Five S’s of Pasture improvement and management - Fertiliser management: Phosphorus - Soil loss factors – phosphorus - Capital applications of phosphorus - Maintenance applications of phosphorus - Animal loss factors - Soil testing - Pasture establishment: steps in process - Why re-sow pastures? - Pasture establishment – costs to consider - Pros and cons of direct drilling - Weeds and herbicides – main approaches - Modes of action – herbicides - Redlegged earthmite - Cockchafers - Slugs - Black field crickets - Herbicide treatments - Winter cleaning - Spray topping - Spray grazing Feeding and Nutritive values of pastures - Measures of pasture quality - Feeding value – definition - Nutritive value – definition - Energy definitions - Digestibility - Pasture quality - Factors influencing nutritive value - Nutritive value of plant species - Effect of plant maturity on nutritive value - Effect of season on nutritive value - Effect of season on ME content - Feeding value of pasture species - Effects of leaf stage at grazing on pasture growth and nutritive - characteristics - Factors controlling intake – pasture/management factors - Effect of pasture DM-on-offer and quality - Pasture targets for optimizing intake - Factors controlling intake - Components of intake Equation - Preference vs selection - Preference for legume and grass - Selective grazing – green and dead matter - Selective grazing – patch effect Grazing Management - Set Stocking - Objectives of grazing management - Elements of grazing management - Importance of stocking rate - Importance of stocking rate – graphs - Effect of stock management policies - calving date example - Grazing method - Grazing method – experiment - Continuous stocking - Rotational grazing - Rotational grazing versus set stocking - Other grazing methods - Feed planning tools - Feed profile - Feed budget - Information needed for feed profiling - Important pasture cover targets – dairy - Important pasture cover targets – sheep and beef cattle - Feed budgeting - Information needed for feed budgeting - Making feed plans work Fodder Conservation - Why conserve fodder? - Variability under grazing - Principles of fodder conservation - Objectives of fodder conservation - Quality of conserved fodder - Hay-making process aim - Hay-making process - Factors affecting hay drying rate - Hay losses - Respiration loss - Limiting respiration loss - Mechanical losses - Storage losses – mould - Spontaneous combustion of hay due to mould - Browning reaction - When to bale - Quality of hay - Issues to consider when purchasing hay - Biochemistry of silage making - Processes in silage making - Fermentation process - Important factors for silage - What is good silage? - Suitability of different crops for silage - Ease of ensiling - Losses during silage making - Rules to minimise silage losses - Plant respiration - Spoilage – silage - Prevention of spoilage – silage - Additives and inoculants for silage - Key points – silage - Silage vs. hay Endophytes and forage crops - Why conserve fodder? - Variability under grazing - Principles of fodder conservation - Objectives of fodder conservation - Quality of conserved fodder - Hay-making process aim - Hay-making process - Factors affecting hay drying rate - Hay losses - Respiration loss - Limiting respiration loss - Mechanical losses - Storage losses – mould - Spontaneous combustion of hay due to mould - Browning reaction - When to bale - Quality of hay - Issues to consider when purchasing hay - Biochemistry of silage making - Processes in silage making - Fermentation process - Important factors for silage - What is good silage? - Suitability of different crops for silage - Ease of ensiling - Losses during silage making - Rules to minimise silage losses - Plant respiration - Spoilage – silage - Prevention of spoilage – silage - Additives and inoculants for silage - Key points – silage - Silage vs. hay - What is an endophyte? - Where are endophytes found? - Why do we use endophytes? - Endophyte terms - Ryegrass endophyte - Endophyte in Perennial Ryegrass – Alkaloids - Threshold levels – alkaloids - Seasonal patterns in alkaloids - Summary of Endophyte strains and the Alkaloids they produce - Ryegrass Endophyte – trial results - PRGT – cost to industry - Summary of Ryegrass endophyte - Endophyte in Tall Fescue - MaxP advantages and disadvantages - Winter and summer crop options - What is a forage crop? - Roles of forage crops - Winter cereals - Spring sown canola - Turnips - Regrowth Brassicas - Millet and Sorghum - Chicory – growth patterns - Chicory - Chicory grazing management - Conclusions – forage crops