Cleaning machinery prevents spread of seed and animal disease

Taking unwashed machines from one farm to another risks spreading disease

Moving farm machinery from one county to another, from one farm to another farm, or even from one field to the next field, has the real possibility of transferring seeds and diseases that can affect both plants and animals. How easy it is to finish one job, pack the harvester or spreader for transport, and drive off down the road to the next farm - or load the machine onto a truck or trailer and move it hundreds of miles to the next farm which needs the service. 

The huge size and cost of farm machinery today means that many machines have multiple users, through contractors, machinery rings and co-ownership. Don't think it's a new phenomena, as contractors and custom harvesting, ploughing and other work has been done for over 150 years, as the threshing gang moved from one farm to another, and ploughing work was done with traction engines and huge beam ploughs. But today more of the work, be in combining or muck and slurry spreading, is done in the field rather than in the yard, so the opportunity for weed seed and disease distribution is perhaps greater.

The Ash tree die-back disease shows how virulent and aggressive plant diseases can be, and how easily they can be inadvertently moved many hundreds of miles. 

Larry Steckel, an associate professor at the University of Tennessee Dept of Plant Sciences, says that farmers' and contractors' machinery is one of the main reasons why glyphosate-resistant pigweed is spreading into new areas such as mid Tennessee where it has never been before. The consequence is a sharp rise in the cost of weed control, which has increased ten-fold in the USA.

Larry says that, in the case of pigweed, harvesting equipment is the common culprit. 

"The weed seeds are mature", he says, and so ready to germinate once they have dropped off the machine. In many cases their new field will soon be cultivated into a stale seedbed which the RoundUp resistant weeds will thrive.

Animal disease is as important

Disease pathogens that affect livestock are also carried in muck and slurry spreading equipment, and it is quite possible for disease to be carried from one farm to another this way.

In the latest issue of Farm Ideas (Vol 21 issue 3) one farm visited has a high health pig breeding unit which was completely isolated from the outside. Nobody, including the regular staff, inspectors, or the owners themselves, entered the pig unit without first showering and putting on clean clothing. Compare this with the precautions taken by many livestock farms where spreaders come in from other farms without being washed. 

Not all are like this - in fact one dairy farm local to our office built his own umbilical slurry spreading kit rather than use a contractor precisely to prevent disease being introduced from other farms. 

Cleaning off machinery with brush, air or pressure washer

Using a simple rake to pull off loose material from the header and other places where seed and straw accumulate, and follow this with a broom for the seeds, reduces the quantity carried from one field to another.

A blast of air from a compressor or, as one reader showed us some five years ago, from a 2-stroke leaf blower, makes a better job and costs little more. The leaf blower was kept in the cab and used to every dinner time to clean off the air intake and other parts.

The pressure washer cleans even better of course. But when it comes to the spread of blackgrass and other diseases, the time taken might seem a small sacrifice to make. Devising a mobile washer with it's own tank and engine driven pump is not rocket science. 

Farm Ideas issues of interest are:

Vol 12 - 3  Home made boot scrubber / disinfector

Vol 12 - 4  Home built umbilical slurry spreading machine.

Practical Farm Ideas features innovations developed by farmers, contractors and small engineers, whose contributions, which are always included free of charge, are welcomed. Please email the editor