Simple spray procedures for
spraying Herbicides using Matabi knapsack sprayer
Based on the most common errors that I have been observing with the use
of the Spanish Goizper Matabi knapsack sprayer
The procedures listed below apply to all makes of sprayers
Setting up new Agrichemical
Always first read the instructions that come with the spray equipment
in particular regarding the pressures and nozzles to use for Herbicide
Use the slots provided and the method indicated to attach the straps
Setting pressure gauge
Set the pressure gauge so that the red dot shows for spraying of
herbicides because it is recommended to use a pressure of 1.5 bar,
which is indicated by the red dot on the pressure regulator.
Selecting correct nozzles for
Always insert and only operate with the nozzle filter in place. For our
application the only nozzle to use is the yellow flat fan nozzle
provided together with the sprayer. Supervisors are to make regular
checks to see that that the filters are clean and are in place.
Only use the following nozzles supplied with the Matabi knapsack sprayer
Low drift flat fan spray nozzles
Low drift flat fan spray nozzles for spraying herbicides
These nozzles are designed to reduce the drift with good coverage at
1.5 bar. These nozzles are especially recommended for systemic
These nozzles are wide angle nozzles for herbicide application, they
are mostly used for pre-emergence herbicide spraying when a larger
droplet size is required.
The other nozzles supplied with the Matabi knapsack sprayer are
designed to operate at 3 bar giving a smaller droplet size for the
spraying of pesticides. The smaller droplet size vastly increases the
spray drift increasing the use of herbicide and increasing the danger
of damage to non-target plants
The operator adjustable nozzles supplied with the Matabi knapsack
sprayer are not to be used under any circumstances for the spraying of
herbicides because they are not designed for the application of
herbicides in the field resulting in overdosing and in most cases
wasting tank mix. They are designed to be used for spraying flies in
USING THE INCORRECT NOZZLES WASTES CONSIDERABLE AMOUNTS OF TANK MIX
THIS BAD PRACTICE REQUIRES THE USE OF FAR MORE HERBICIDE CONCENTRATE
THIS BAD PRACTICE REQUIRES THE USE OF FAR MORE WATER
THIS BAD PRACTICE GREATLY REDUCES THE AREA SPRAYED PER DAY COMBINED
THE ADDITIONAL COST OF HERBICE THE EXTRA NEED TO SUPPLY WATER AND THE
REDUCED AREA SPRAYED DRAMATICALLY INCREASES THE COST OF SPRAYING
Care of spray equipment
Rule number one is to keep the sprayer clean at all times in particular
on the inside to prevent clogging of the filters and nozzle which
disturbs the spray pattern and usually ends in the nozzle blocking
completely This wastes both the time to clean out the equipment and
requires that the herbicide in the tank be discarded.
Never sit on spray equipment Matabi knapsack sprayers are not seats.
Never treat the sprayers roughly such as simply throwing spray
equipment onto or off of the back of a truck or van.
Take care to prevent damage to the spray lance and nozzle. At no time
allow the nozzle to be stuck into the ground. When finished using the
sprayer lock the pump handle with the devise provided and store the
spray lance in the place provided
Only use spray equipment that is in good working order, always check
spray equipment before use.
Always check nozzles for cleanliness and correct spray pattern before
Always check to see that the spray trigger is cutting off the supply of
mixed herbicide completely when it is released.
Always check for leaks when under pressure check that the cap is
sealing so that the tank mix cannot pour out onto the back of the
Never leave sprayers under pressure when transporting from site to site
Never leave sprayers with mix in the tank overnight.
Cleanliness when working with
Always have a bucket on site with plenty of clean water in it for
washing hands when handling Herbicide concentrates and spray equipment.
Always have soap and cloths or towels on site as well
Always keep the chemical and water containers clean in particular blue
dye containers, always wash dye concentrate that spills onto the
container or onto hands or gloves off immediately.
THERE IS ABSOLUTELY NO ACCEPTABLE EXCUSE FOR CONTAMINATING HERBICIDE
CONCENTRATE CONTAINERS; WATER CONTAINERS; SPRAYERS AND VEHICLES WITH
Always wash out the sprayer at the end of the day with fresh water and
pump clean water through the sprayer to purge it of all chemical
Always wash out nozzles and filters after use, to prevent clogging of
the filter and nozzle this is of particular importance when using blue
At the end of the day remove the nozzle and filter and place into a
plastic jar filled with soapy water
Always use clean water free of contamination for making the tank mix.
Always keep water containers closed so that contamination cannot enter
Do not allow contamination to enter the spray tank.
Always use a clean measuring jug for measuring agrichemicals to avoid
contamination from entering the spray tank
Always wash the measuring jug after use.
Always check that the measuring jug is free from contamination before
each and every use, failure to do so causes blocked nozzles that affect
the spray pattern giving poor coverage and reduces spray speed and
above all wastes time and tank mix.
Always keep herbicide containers, sticker containers and blue dye
containers clean especially around the filler and cap to prevent
contamination of the tank mix and to prevent contamination of the
person mixing the agro-chemicals
Mixing and Use of Herbicides
Always read the label before use and apply in strict accordance with
the legal provisions of the label.
Do not ever spray herbicides in or near sensitive natural
areas that contain PICLORAM see here for more
Selecting the correct Herbicide
for the Job
Always use the recommended application rate or less for
Always apply the correct amount of herbicide adjusted in regards to the
specie being sprayed, the weather and the growth of the target plants.
The more favorable the growing conditions the more that the herbicide
to be applied can be reduced.
Spray different plants species with the appropriate herbicide and
concentration for each specie
Make a chart of commonly sprayed species for quick easy reference
Using more than the optimum
amount of herbicide does not produce better results
The following factors need to be observed for optimum results and the
dose rate adjusted accordingly
Time of year
Soil moisture content
Stage of growth
Rate of growth
Specie being sprayed
Correct sticker, spreader, penetrant for each herbicide and specie
Make a chart of commonly sprayed species with recommended herbicide and
application rate for quick easy reference
Always use a clean well calibrated measuring jug that gives accurate
measurements in particular when small amounts of herbicide are being
added to the tank mix. A small error that adds more herbicide than
required to the tank mix per tank can make a huge amount of wasted
herbicide at the end of a month when a large team is at work.
Avoid contamination of skin or clothing with Herbicide concentrate. If
contamination accidently occurs, wash immediately with soap and water
The larger the amount of herbicide that can be mixed at a time the more
accurately it can be mixed reducing wastage of herbicide as well as
saving considerable time that goes into mixing individual tank mixes.
Ensure that no herbicide
concentrate gets spilled onto the ground.
Dish washing liquid in particular Sunlight liquid is an excellent
wetter, sticker, penetration promoter.
Never spray up into the air at a height of over one meter in windy
conditions due to excessive spray drift.
Do not under any circumstances allow spray drift to contaminate areas
not to be sprayed.
broad leaf herbicides in
near to trees because spills
will probably result in damage to or the death of the tree in time.
Spilling even the very smallest amount of herbicide in particular PILCORAM
while mixing under trees
can cause this to happen
Always partially fill the tank with water before adding the chemicals
then top up to the desired level once the agrichemicals have been added.
Personal protective equipment
Spray operators are to only apply herbicides if they are wearing full
PPE required for use by spray operators.
Overalls should be removed and washed after each days spraying.
Eye protection and gloves must be washed before use each day.
Never put on contaminated gloves, eye protection or respirators.
Boots are always to be kept clean and in good condition
Spraying and the use of spray
Use staff that have been correctly trained and that have been clearly
Monitor performance of the spray operators for bad spray habits and
Calibration of the equipment is important on the Matabi knapsack
sprayer of main concern is that the correct spray pressure and nozzles
are being used for the job.
The walking speed and coverage to near runoff must be constant
The height that the spray nozzle is being held above the plants must be
correct and constant
If held too high in the air the amount of spray drift increases
considerably under windy conditions.
The operator MUST ALWAYS ONLY spray with the wind on his or her back.
NEVER EVER allow a spray operator to spray directly into the wind in
particular on a windy day.
Ensure at all times that the spray operator or bystanders do not get to
breath in spray drift in particular herbicides containing Picloram.
Beware Picloram is very toxic if inhaled and is harmful to the eyes so
do not allow spray be breather or to enter
the eyes and if it does always have plenty of fresh water in a bucket
on the spray site with soap clean water and a towel to was the
Always have a first aid box with appropriate eye wash
Do not spray if the plants are wet in the early morning or after rain
as it greatly lessens the effectiveness of the spray.
Do not spray if it is likely to rain after spraying, check on the
herbicide label for details for each and every herbicide combination
Used chemical containers
Do not leave lying about remove the same day from site and dispose as
Never let the staff or anyone else use used containers for the storing
of drinking water or for use at home.
View or Download
Herbicide Application Guide Here