Transcript Weed Control - Michigan State University

Weed Control
Topic 2044
Mr. Christensen
Typical Michigan Weed Seed
Production
Weed
seeds/plant weed density crop
Velvetleaf 400-1,500
90
corn
Giant foxtail 2,500
100
corn
Common
Lambsquarters 57,000
8
soybean
Weed Seed Fate
From Michigan Field Crop Pest Ecology and Management-Michigan State University Extension Bulletin E-2704
Integrated Pest Management
• Integrated pest management--is the use of
all appropriate and economical strategies to
manage pests and their damage to
acceptable levels with the least disruption to
the environment.
Integrated Pest Management
• Determine goals
• Pest Monitoring-what kind, how manytiming
• Pest Identification and threshold/action
levels
• Control strategies available, implementation
and evaluation of success or failure
• Record keeping
Techniques Used in Pest
Management
• Natural controls-climate, natural enemies,
geographic barriers, food and water supply
and shelter
• Applied Controls-Host resistance,
biological control, cultural control,
mechanical control, habitat modification
and sanitation and chemical control
Methods of Weed Control
• Cover crops—weeds don’t have a space to
grow.
• Crop rotation—The more diverse the
rotation the less opportunity there is for
weed population to grow.
• Tillage—No till leaves weed seeds on or
near the soil surface, seeds in the
germination zone decrease.
Methods of Weed Control
• Planting date—Weed competitiveness can change
with planting date.
• Crop plant population and row spacing-Heavier
planting limits light for weed germination.
• Rotary Hoeing—Removes small weeds and lets
the crop get a head start.
• Cultivation—Do not cultivate if weeds are not a
problem or aeration is not needed it can cause
weed seeds to be brought into the germination
zone.
Cultivation
Chemical Controls
•
•
•
•
Algaecide-Algae
Biocide-Microbial Org.
Fungicide-Fungi
Insecticide-Insects &
Related animals
• Herbicide-Weeds
• Miticide-Mites
• Nematicides-Nematodes
•
•
•
•
Rodenticide-Rodents
Avicide-Birds
Piscicide-Fish
MolluscicideSlugs/snails
• Ovicide-Eggs of
organisms
• Predacide-Vertebrates
Other Chemical Controls
• Growth regulator-modifies plant or insect
development
• Defoliant-removes plant foliage
• Desiccant-dries plant foliage
• Repellent-diverts a pest
• Attractant-lures a pest
• Pheromone-attract pest or disrupt behavior
• Sterilan-renders pest unable to reproduce
Pesticide
•
•
•
•
•
Protectants
Sterilants
Selective
Nonselective
Broad-Spectrum
•
•
•
•
Contact
Systemic
Persistent
Nonpersistent
Pesticide Categories
• Non-Selective—Kills or adversely affects
many organisms (Glyphosate)
• Selective—Effective against one type of
organism and not another.
• Broad-Spectrum—Pesticides that control a
wide range of pests (multiuse).
• Contact—Kill or adversely affect the target
organisms by simple contact.
Pesticide Categories
• Systemic—Absorbed by one part of an
organism and distributed internally to other
parts of the organism for action (heartworm
control in dogs)
• Persistent—Remain active for a period of
time giving residual protection.
• Non-persistent—Control pests at time of
application and breakdown quickly.
Pesticide Categories
• Protectants—Pesticide applied to prevent
pest establishment.
• Sterilants—Pesticide that manage pests by
rendering them incapable of normal
reproduction.
Chemical Weed Control Modes
of Action
• Growth Regulators—Banvel, Stinger, 2,4-D
(Amine and Ester)
• Amino Acid Synthesis inhibitors (ALS
synthase enzyme)—Accent, Broadstrike,
Harmony, Pursuit.
• Amino Acid Synthesis (EPSP synthase
enzyme) inhibitors—Glyphosate (Honcho,
Ranger, Roundup)
Chemical Weed Control Modes
of Action
• Lipid (Acetyl-CoA carboxylase enzyme)
inhibitors—Assure II, Fusion, Poast, Whip
• Seedling root (tubulin protein) inhibitors—
Balan, Prowl, Sonolan, Treflan
• Seedling Shoot inhibitors—Arena, Dual,
Eptam, Lasso, Surpass, Frontier
Chemical Weed Control Modes
of Action
• Photosynthesis (D-1 Quinone-binding
protein) inhibitors—Atrazine, Basagram,
Bladex, Buctril, Spike.
• Membrane disrupters—Avenge, Cyclone,
Gramoxone Extra, Cobra, Reflex, Blazer
• Pigment inhibitors—Command, Zorial
• Why are their so many Modes of
action?
• What advantages do they give the
grower.
• Some are effective against different weeds.
• Timing of the pest problem may dictate
what can be used (pre-emergence, post
emergence)
• Some last a long time and cause safety
problems with the fruit or following crops
• Using the same chemicals may develop
resistance in the pest
Developing Resistant Pests
From Michigan Field Crop Pest Ecology and Management-Michigan State University Extension Bulletin E-2704
Glyphosate Resistant Weeds
Marestail
Black nightshade
Waterhemp
Yellow nutsedge
Velvetleaf
Common Ragweed
Successful Farming February 2004
Lambsquarters