Linkage Sprayers Product Information (13176 Kb) - Fatcow

SPRAYING IN STUBBLE AND
SMALL TARGETS
Spraying in Stubbles
The sharp increase in minimum tillage and no till
farming has left many paddocks with a heavy stubble
load. In those situations it is difficult to penetrate the
stubble cover and achieve satisfactory coverage on
the ground. Getting trapped on stubbles generally
inactivates most herbicides. Many trials have shown
that anticipating losses and choosing a robust product
rate is most beneficial for efficacy. So is an increase
in water volume and spray quality. COARSE or VERY
COARSE droplets have more potential to bounce of the
stubbles and land on the ground or target underneath.
Top Tips
• Increase product rate
• Increase water volume
• Increase Spray quality to
COARSE – VERY COARSE
• Decrease fan angle in erected stubble
• Increase spray height in erected stubble
(only with minimum COARSE spray quality)
• Consider using the TurboDrop nozzle.
In erected stubbles the vertical structure of the stubble
row interferes with the side movement of the spray fan
and can filter out spray droplets. Options to improve
efficacy are to decrease the spray angle by using less
than a 110° nozzle and to raise the boom height (only
when using COARSE to VERY COARSE spray quality –
be aware of drift!) to allow droplets a more vertical fall.
This makes the agrotop TurboDrop to an ideal nozzle
for stubble application. It produces a COARSE to VERY
COARSE spray quality. On the paper the nozzles
should produce a 110° fan angle but in reality it is
more a 95°–100° angle.
Spraying Small Targets
In broadacre spraying the applicator manipulates
coverage mainly through droplet size and water
volume. The likelihood to hit small targets can be
increased with higher water volumes or by producing
more droplets with a finer spray quality. If only few
droplets hit a target using robust product rates increase
the likelihood of delivering the lethal dose. In general,
if coverage on small targets becomes a critical issue
increasing the water rate is more efficient than using
smaller droplets.
Most robust results on small targets are generally
achieved with water rates above 80 L/ha. Many trials
over recent years indicate that control of even small
grass targets, when using these water rates, is at least
as reliable with a COARSE spray quality as it is with a
FINE/MEDIUM spray quality.
To optimise application when targeting small grasses
it is advisable to increase water rates, regardless of
spray quality or chemistry. If water rates are low (40–
70 L/ha) a FINE/MEDIUM spray quality is likely to be
more successful than a COARSE spray quality – under
ideal conditions. Under adverse weather conditions,
wind or heat may reduce the efficacy of a FINE droplet
application to below the efficacy levels of a COARSE
droplet application.
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www.croplands.com.au
Photos are for illustrative purposes only. Prices and specifications are subject to change
without notice. Prices effective January 2013. For indicative freight prices, see page 103.