1. Herbicide application

2. Factors that may influence the efficacy of the applied
herbicide
• Type of weed and density
• Choice of product
1. Formulation
2. Rate of application
3. Mode of action
 Timing of the treatment
1. Early preplant (EPP)
2. Preplant foliar (PPF)
3. Preplant incorporated (PPI)
4. Pre-emergence (PE)
5. Post emergence overtop (POT)
6. Post emergence directed (POE-
DIR)

3. Factors that may influence the efficacy of the applied herbicide-Contd.
 Water management
 Equipment inspection and maintenance
 Calibration and calculation dose to apply
 Application techniques
1. Aerial application
2. Ground
• Tractor mounted boom
• Knapsacks or Backpatch
i. Broadcast
ii. Band
iii. Spot
iv. Directed

4. Factors that may influence the efficacy of the applied herbicide-Contd.
 Weather condition
 Safety

5. Calibration of Spray volume rate and herbicide concentration

6. Timeliness in herbicide application
This is critical to the effectiveness of the herbicide and
to the efficiency of the operation. Herbicide application
should be made when the weeds are most susceptible
and when environmental conditions are suitable for
effective and safe application. Herbicides therefore,
should be
applied under the following conditions:
When the energy reserve in the weeds are low
When they are some fully expanded soft leaves
When the weeds are young and are actively growing
When it is not raining but the soil moisture is adequate

7. General steps for effective herbicide application
1. Read the label
2. Wear protective clothing and equipment mentioned
on the label, such as goggles, gloves, etc.
3. Make certain you have the correct equipment for
herbicide application.
4. Mix herbicide for use according to the label, using
the exact proportions.
5. Choose the best day and time of day for safety in
herbicide application.
6. Apply herbicides in a continuous manner with little
overlap.
7. Clean up after herbicide application.
8. Store herbicides in original containers in a locked
cabinet away from temperature extremes and away
from children and pets.
9. Know what first aid procedures are required by
reading the "Statement of Practical Treatment" on
the herbicide label ahead of time.

8. Three Common Nozzles
• Cone nozzles
• A fan nozzle
• A Floodjet
• flat fan
• deflector
• Low volume(LV)
• Very low Volume

9. TABLE: 2. Deflector nozzle: LV nozzle
with lance at 50 cm above ground
(L/ha)
Nozzle
colour
code
Flow rate
(L/min)
Swath
(cm)
Rate
Yellow 0.6 50 200
Green 1.2 100 200
Blue 1.8 150 200
Red 2.4 200 200

10. TABLE: 3. Deflector nozzle:VLV nozzle
with lance at 50 cm above ground
Nozzle
colour code
Flow rate
(L/min)
Flow Swath
(cm)
Rate
(L/ha)
Orange 0.24 110 35
Green 0.40 144 50
Yellow 0.47 170 45
Blue 0.68 160 70

11. Thank you….