The problem of off-field drift of chemicals used in agrotechnical treatments is important for two reasons. Off-field drift of plant protection products or fertilisers can cause environmental risks.
Surface waters can be directly polluted if the drift of the chemicals applied is towards them. The way to prevent chemical drift is, first of all, to choose treatment dates such that the weather is suitable, such as:
- wind speeds of less than 4 m/s,
- temperature appropriate to the nature of the chemical or fertiliser,
- not during or before the rain.
In orchards, it is best to use tunnel sprayers, and for field spraying, sprayers with auxiliary air flow and anti-drift nozzles. In addition, it is important to maintain adequate buffer zones, i.e. distances from other crops, non-agricultural land or surface water.
Some mineral fertilisers are in a dusty form, which poses a risk of being blown off-site with the wind. When planning liming with a dusty fertiliser (e.g. calcium oxide CaO), the following limitations should be taken into account:
- treatments should be carried out under appropriate weather conditions,
- additional equipment, so-called dust suppression adapters, should be used for fertiliser spreaders.
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