Chavtrac and HSE comment on air assisted spraying


Pontypool 27 Mar 97:

The latest statement from HSE in which they reiterate their refusal to relax weather guidelines for crop spraying is largely welcomed by Chavtrac. We feel it is necessary for sprayer operators to be seen to be acting responsibly in this matter and stay within the guidelines arrived at over many years experience.

Air assisted sprayers should not be seen as an excuse to continue spraying in windy conditions. Scientific and anecdotal experience would suggest that there is a slim theoretical basis for air assisted sprayers to have any special dispensation for spraying in windy conditions. Twin fluid nozzles allow the operator to quickly select a coarser droplet size which inevitably leads to inferior coverage. If droplet size is increased to prevent drift then coverage is often inferior. Droplets containing air will always be lighter which of course leads to a droplet more easily carried by air currents.

Air curtain type sprayers may lead to increased drift where crop height and density are insufficient to contain the air flow.

Chavtrac have researched, developed and promoted the high speed spraying system which allows the sprayer operator to spray at low water volumes but with much increased coverage. The system demands a special high powered vehicle with specialised aerodynamics and independent suspension. Operators using the Spra Coupe have reported outputs of up to 1000 acres per day which allows spraying to be carried out effectively on days when weather conditions fall within the accepted guidelines for crop spraying. When conditions are not suitable for spraying then the the operator - with his spraying program up to date can afford to wait for weather conditions to improve.

Recent trials from Morley research station in Norfolk echo earlier work carried out at Silsoe College and show that spraying at high speeds with specialised equipment produces superior coverage with reduced environmental impact. - Contact Chavtrac for more details.