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Chilean needle grass ( Nassella neesiana ) Integrated grazing for success

Chilean needle grass ( Nassella neesiana ) Integrated grazing for success. Charles Grech 2/11/05 DPI Agricultural weeds. The problems . Chilean needle grass ( Nassella neesiana ) Low feed value & physical damage to livestock when in seed replaces more productive improved pasture species

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Chilean needle grass ( Nassella neesiana ) Integrated grazing for success

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  1. Chilean needle grass (Nassella neesiana) Integrated grazing for success Charles Grech 2/11/05 DPI Agricultural weeds

  2. The problems • Chilean needle grass (Nassella neesiana) • Low feed value & physical damage to livestock when in seed • replaces more productive improved pasture species • invades native grasslands and conservation zones • Seeds dispersed by adhering to machinery & animals • Stem seeds and basal cleistogenes

  3. Grazing management PhD • Two National projects: • Chilean needle grass Regional Best Practice Management • Grazing management for long term utilisation and control of Chilean needle grass • To determine the stock density, species of grazer and time of grazing to maximise animal production • Supervisors • Dr Brian Sindel - The University of New England, Armidale • Dr David McLaren - Department of Primary Industries, Frankston • Dr David Chapman - The University of Melbourne, Parkville

  4. Trials underway... • Regional Best Practice Management • NSW & Vic • Feed evaluation of Chilean Needle Grass • fertiliser and clipping • spraytopping • Reducing seed production • Comparison of stock class for Chilean Needle Grass grazing • Time of Burning • Time of Slashing • Competition and Selective manipulation • Pasture Species Competition • Soil Fertility and pH • Herbicide wiper

  5. Chilean needle grass Regional Best Practice Management • The majority of knowledge concerning CNG comes from a study undertaken at one location (near Armidale, NSW) • seed production appeared to be sensitive to rainfall, • interaction of temperature and rainfall. • This makes the generalisation of management recommendations from one region to the next questionable

  6. Chilean needle grass Regional Best Practice Management • Four regional trial sites • Glen Innes NSW (Property of Col & Andrew Say ‘Euroa’) • Goulburn NSW (Property of Tony and Donna Kent ‘Dambreezi’) • Toolleen Vic (Property of Roger & Brian Hickson ) • Greenvale Vic (Property of Ian & Margaret Souter ‘ The Elms’) • Sites managed with regional staff - DPI NSW & VIC • Lori McWhirter • Jeff Lowien • Natasha Baldyga • Brad Westhead

  7. Chilean needle grass Regional Best Practice Management • Treatments (applied autumn 2003 onwards) • Herbicide (Glyphosate; non selective & spraytopping, Flupropanate) • Sheep grazing (strategic grazing, set stock, lockup) • Resowing (pasture, cropping) Greenvale, Toolleen, Goulburn Glen Innes

  8. Effect of grazing regime on desirable perennial grass basal cover in glyphosate plots - Toolleen d569 30 24 Lockup & Resow 20 % cover 11 Strategic graze & 10 Resow 0

  9. Strategic grazing after Flupropanate application (Winter 2003) • significantly less CNG than set stock plots - Toolleen Dec04 Set stock Strategic Winter 2004 Spring 2004 Autumn 2005

  10. Chilean needle grass Regional Best Practice Management • Trends so far… • Flupropanate • reduced CNG cover • proportional to grazing • broadleaf weeds • Glyphosate (& sow) • reduced CNG • increased perennial

  11. Feed evaluation of Chilean needle grass Fertiliser addition & Clipping • Low feed value in contrast with producer observations • Feed value quantified throughout growing season (FeedTest) • compared to cocksfoot (Dactylis glomerata) • Trial conducted at Greenvale Victoria (Property of Ian Souter) spring 2003 to winter 2005

  12. Feed evaluation of Chilean needle grass Fertiliser addition & Clipping • Treatments • Clipped regrowth Vs unclipped growth • Fertiliser addition A 250kg/ha single super phosphate (8.8%P 11%S 19%Ca) B 200kg/ha urea (46%N) –split fertiliser applications of 100kg/ha over spring 2003

  13. Feed evaluation of Chilean needle grass Fertiliser addition & Clipping • Results since spring 2003… • Clipped CNG continues to have significantly more ME (2003 & 2004) • N fertilised - significantly more ME at day 63 & day 398

  14. Feed evaluation of Chilean needle grass Spraytopping • Feed value quantified throughout growing season (FeedTest) • compared to phalaris (Phalaris aquatica) • Trial conducted at Bannockburn (Hamilton Hwy) Victoria spring 2003 • Treatments • Two spray times, linked to growth stage • Two spray rates (Glyphosate)

  15. Feed evaluation of Chilean needle grass Spraytopping • Effect of spraytopping • irrespective of time of spray & rate of spray • Plants that were spraytopped (both CNG & Phalaris) • significantly higher dry matter percentage (DM%) • significantly lower fibre content (NDF) • Application rate (both CNG & Phalaris) • no significant responses

  16. Feed evaluation of Chilean needle grass • Clipped CNG - significantly more ME than unclipped (2003 & 2004) • N fertilised - significantly more ME than non N at day 63 & day 398 • Spraytopped Plants (both CNG & Phalaris) • significantly higher dry matter percentage (DM%) • significantly lower fibre content (NDF)

  17. Effect of Stock Class on Chilean needle grass seed production • CNG can be valuable winter feed when in its vegetative state • Grazing is a means to reduce seed production • Cattle graze CNG better than sheep

  18. Effect of Stock Class on Chilean needle grass seed production • Trial established to quantify the amount of standing seed remaining after grazing by sheep or cattle in different grazing regimes. • Animal production • pasture changes • Treatments initiated spring 2004 ongoing • Cattle Vs Sheep • Angus cows and calves • Suffolk X ewes and lambs • Rotational Vs Set stock grazing • 12DSE/ha equivalent • 4 paddock time based rotation

  19. Trial layout • Greenvale VIC • property of Ian Souter • Managed by John & Alan McKenzie • Weed CRC summer student Aaron Dodd • 30ha trial area

  20. Effect of Stock Class on Chilean needle grass seed production • Trial Measurements • Standing CNG seed • panicle and stem • seed set harvest • Pasture regrowth after grazing • Growth composition • BOTANAL • Pasture composition change • Basal observations • Ground cover • Animal liveweight & condition score • Monthly • Fleece VM

  21. Results - Seed production • Grazing cw. ungrazed • reduced standing seed • panicle • stem cleistogene • Cattle cw. Sheep • cattle grazed more than sheep • approx 100 seeds/g

  22. Results - Pasture regrowth • Grazing cw. Ungrazed • BOTANAL (pasture cages) • early spring (d56) • grazing reduced CNG

  23. Results - Animal production • Sheep Vs Cattle • Liveweight (kg/ha, DSE/ha) • Welfare

  24. Stockclass conclusions • Grazing • significantly reduced CNG seed production (panicle & stem) • changed early spring regrowth to a more palatable composition • Cattle significantly more effective than sheep • Managed grazing with cattle to reduce seed production

  25. Time of Burning - Chilean needle grass • Burning can sterilise weed seeds both on the plant and in the soil seedbank • Trial conducted at Greenvale Victoria (Property of L&J Karmel). • Summer 2004/2005 ongoing

  26. Time of Burning - Chilean needle grass • Treatments • 3 burning times • 20x20m plots • drip torch strip ignition(leeward side)

  27. Time of Burning - Chilean needle grass • No effect of time of burn as yet... • Burning prior to seedfall reduced panicle seeds left standing • patchy burns • Burning significantly increased CNG seedlings when compared to unburnt • decreased vegetative litter • increased bare soil Early summer Mid Summer Autumn

  28. Time of Slashing - Chilean needle grass • Slashing reduces dry matter during reproductive phases • reduced panicle seeds (regeneration) • Vector for the spread of CNG. • Evaluation of different times of slashing related to CNG growth stage • Trial conducted at Greenvale Victoria (Property of L&J Karmel). • Summer 2004/2005 ongoing

  29. Time of Slashing - Chilean needle grass • Treatments • 7 slashing combinations • 5x20m plots • 3 point linkage rotary slasher

  30. Time of Slashing - Chilean needle grass • Time of slashing (from 2004 only) • no effect on seedlings in following season • no effect on botanical composition • CNG • Desirable perennials • litter (Dec Slash)

  31. Pasture competition - species • Pasture competition can make soil resources unavailable to weed species • This trial evaluated the competitiveness of 3 pasture species at different sowing & fertiliser rates. • Trial conducted at Wildwood Victoria (autumn 2004), on the property of Robyn Kissel ‘Grevisfield.’ • non arable infestation of CNG.

  32. Pasture competition - species • Treatments • 3 species • Phalaris aquatica, • Dactylis glomerata • Festuca arundinacea • 2 sowing rates • 2 fertiliser rates (Di ammonium Phosphate) • 45x20m plot area (one grazing cell), • Sowing using all terrain disc seeder (RockHoppa by AgReCon) • Tractor fitted with high flotation tyres (Trelleborg) • The trial plots were made up of 30 grazing cells across 15 lanes of a 16 lane grazing system operating on a 90-100day rotation stocked equivalent to 35DSE/ha (Cattle).

  33. Pasture competition - species • A Control plots were not fertilised or sown to any pasture species • B Jessup MaxP Tall fescue (Festuca & Goulburn Subterranean clover. • C Kara Cocksfoot (Dactylis glomerata) & Goulburn Subterranean clover. • D Holdfast Phalaris (Phalaris aquatica) & Goulburn Subterranean clover. • E Seed rates • Jessup MaxP Tall fescue (Goulburn sub clover) Normal rate 22kg/ha (6kg/ha) • High rate 44kg/ha (12kg/ha) • Kara Cocksfoot (Goulburn sub clover) Normal rate 7kg/ha (6kg/ha) • High rate 14kg/ha (12kg/ha) • Holdfast Phalaris (Goulburn sub clover) Normal rate 8kg/ha (6kg/ha) • High rate 16kg/ha (12kg/ha) • Note: Sub clover seed was lime coated and inoculated. Seed rate is expressed as equivalent sowing rate of bare seed.

  34. Effect of Soil fertility and pH • Nassella species may be less responsive to soil fertility than phalaris species • Trial established to evaluate the response of Chilean needle grass to different levels of soil fertility and pH • Glasshouse trial - DPI Frankston Winter/spring 2005 • LaTrobe university honours student James Winters • Treatments (fully factorial) • 3 levels of Phosphorus • 3 levels of Nitrogen • 3 soil pH levels

  35. Effect of Soil fertility and pH • Measurements • seedling vigour (destructive harvest) • mature plants (still growing!) • Results - Response to soil Phosphorus • Seedling height • Phalaris plants significantly higher than CNG (d19 onwards) • Shoot weight • Phalaris plants significantly higher than CNG • Leaf area • Phalaris leaf area significantly higher than CNG (78cm2 vs 19cm2) • Root Length • Phalaris roots significantly longer than CNG • CNG root length increased less than Phalaris in response to P

  36. Conclusion • Feed evaluation of Chilean Needle Grass • fertiliser and spraytopping had limited effects • Reducing seed production/seedbank • Grazing • significantly reduced CNG seed production (panicle & stem) • Cattle significantly more effective than sheep • Burning • reduced panicle seeds • increased seedlings • Slashing • decreased panicle seeds • Competition and Selective manipulation • Herbicide integration • Flupropanate & allow pasture regeneration • CNG slow response to soil Phosphorus

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