Prep Course

Front 1

Non-Chemical Control Methods

Back 1

• Mechanical
• Manual
• Cultural
• Biological

Front 2

Mechanical Control

(non-chemical method)

Back 2

• mowing most common in ROW settings
• disadvantages:

1. must be repeated frequently
2. may increase fire risk
3. cannot be used on steep terrain
4. mowing equipment may throw rocks in road

Front 3

Manual Control

(non-chemical method)

Back 3

• usually involves hand tools/weed eaters/chainsaws
• used most in small area no suitable for mechanical control
• frequent re-treatment necessary (intensive & expensive)

Front 4

Cultural Control

(non-mechanical method)

Back 4

• successful in landscape & ROW settings
• used in conjunction w/ other strategies
• Ex: competitive plantings, irrigating & fertilizing desireable vegetation, mulches & paving)

Front 5

Biological Control

(non-mechanical method)

Back 5

• involves using living organisms to control pests
• most on farm or rangeland settings
• use in landscape and ROW settings impractical
• use control agent (insect) which targets specific weeds - variety of weed present in landscape & ROW areas make this method impractical

Front 6

Chemical Control Categories

Back 6

• selective or non-selective
• pre-emergent or post-emergent activity
• contact or translocated chemicals

Front 7

Selective vs. Non-Selective Herbicides

Back 7

1.) selective

• may only control grass or broadleaf species (very few of this type herbicide are typically not more specific than grass or broadleaf)

2.) non-selective

• control both grass & broadleaf species

Front 8

Two Types of Herbicide Applications

Back 8

*Some herbicides can be both pre-emergent & post-emergent

1. Pre-emergent

• applied before weed seeds germinate
• often applied to soil surface (allow herbicide residues to kill weeds shorty after generation)
• remain effective in soil for long period of time
• most non-selective

1. Post-emergent

• applied after weed seeds germinate
• usually have no soil activity & only work when sprayed on foliage
• can be selective or non-selective
• provide very brief period of control

Front 9

Two Types of Herbicide Applications

Back 9

• contact (kill only above portion of weed)
• translocated (affect entire plant from the roots up)

Front 10

Contact Herbicides

Back 10

• only kill foliage to which they have been applied (in order to kill entire plant entire plant needs to be sprayed)
• most effective for annual weeds, perennial generally resprout the same year
• usually non-selective (kill grass & broadleaf)

Front 11

Translocated Herbicides

Back 11

• transported into plant's vascular system, along with water & nutrients ("systemic" herbicide)
• don't require full coverage
• often prevent perennials from resprouting because they kill above and below-ground
• control of perennials most effective in late summer or fall (plants are sending carbohydrate reserves from top-growth to roots, causing herbicide to travel through roots