Environmental Weeds Flashcards
Types of environmental weeds
Herbs, trees, shrubs, grasses, creepers, suculents
Potential Damage of Enviro Weeds
Decrease Biodiversity - Invade, suppress, exclude native veg, increase fuel load, d.c. amenity
Loss of ecosystem function - alter ecology - water, nuts.
Translocated native plants- coota wattle, costal tea tree
What promotes invasion
Soil disturbance - fire, flood, storms, wind, roads, forestry
ideal invasive attributes
Highly reproductive and short repro cycle Efficient dispersal Lack of natural controls long term survivability rapid growth
Management dilemma faced with enviro weeds weeds
What is cost of damage and control
Who pays
Aims of controlling enviro weeds 4
Preserve and enhance ecological value
Effectively control spread
Manage enviro to prevent incursion of new weed
Rehabilitate disturbed ecosystem
Explain what the aims should be in controlling environmental weeds
ID species Minimise disturbance Time treatments to maximise results Re eatablish appropriate species Integrte controls and reduce adverse affects Monitor and evaluate
Describe some of the IWM control options for environmental weeds
Manual Herbicides Fire Grazubg Mechanical Biological
Advantages of Manual removal
Selective
Minimise disturbance and risk to native veg
Prevent seeding and spread
Effective for small infestations
Dis of Manual removal
Timing limitations
Can spread weeds
Iappropriate for some weeds
Labor intensive and costly
Herbicide Ad
Large infestations Can be selective Can prevent seeding and spread Decrease fuel load Cheaper Minimise soil disturbance
Dis ad Herbicides
Can be non-selective and damage native plants
Can increase fuel loads
Skill required
Operator and public hazards
Types of herbicide control
Aerial Boom Basal bark spray Foliar spot spray Cut stump and paint Stem injection Frill cut and treat Ganule application Weed wiper
Fire ad and dis ad
Cheap
Difficult to control
Timing important for growth stage
Grazing control
NA in NP Goats or steers Palatibility and toxicity Trampling Non-selective Can spread weeds
Mechanical
Cutting
Mowing
Slashing
Temporary
Ad of Biological control of weeds
Selective
Can suppress growth and spread
Value for money
Minimal field labour and enviro effects
Dis ad of Biological control of weeds
TIming limitations Variable results Doesn't eliminate weeds Other controls required Expensive to develop
Burning residues success of reducing weeds
50%
Cultivation success of reducing weeds
0-90%
Clean seed success of reducing weeds
85%
Increase crop competitions success of reducing weeds
50% sowing rates high
Add N
Decrease row spcing
Early Post Emergent Strategy success of reducing weeds
90%
A and B
Achieve, Cheetah gold
Late post Emergent success of reducing weeds
Hay/silage 80%
Manuring 90%
Pre harvest herbicide 70%
Explain what environmental weeds are
Invade natural ecosystem - relatively undisturbed
Outline what is meant by the Bradley method
Work from minimally disturbed sites in towards most weed-infested crops
Minimise disturbance of soil
Allow rate of native plant regeneration to dictate rate of weed removal
Follow up Bradley Methos
Prevent weed regrowth Promote desirable species Remove vacant niches Long term input required Monitor and evaluate
Annual Ryegrass IWM
Pre Sowing Earling Post Emergent Late post emergent Harvest Strategies Rotational Strategies
Pre sowing Strategies
Burning ResiduesCultivationDelayed sowing Clean Seed Increase crop competition Pre Sowing Herbicide Pre Emergent Herd
Pre Sowing Herb %
Double knock 95%
Chaff Collection %
Straw and Chaff Windrows
65%
Rotational Stategies
Other Crops- Herb resistance Canola
Green//brown manure
Hay/silage
Pasture - grazing management, winter clean,, spray topping
Serated Tussock Prevent ion
Clean vehicles
Prevent animal movement
Reduce wind
Prevent feed contamination
Steps to control Tussock
Seed bank management Target seedling Prevent seed set Prevent seed spread Increase ground cover
Contro; techniques of tussock
Glyphosate, 2,2, DPA Manual Grazing management Crpping fire Native Revegetation- plant to trees, doesnt grow in shade
