Bruising becoming an issue as potato harvest gathers momentum
Teagasc is confirming that most growers are now well advanced with the 2021 potato harvest.
Conditions in late September were extremely dry. However, this has led to some bruising on crop where there isn’t enough soil travelling up the webs to cushion the tubers.
Many growers are reporting that crops are slow to die back after desiccation. There have also been a number of comments of poor desiccation on headlands where there is some shading from trees or hedges.
Damage at potato harvest time
Damage at harvest time can cause significant losses in store. In the UK, e.g., it is estimated that harvest damage costs growers in the UK £26 million annually.
According to Teagasc, much of this damage can be offset by setting machines correctly and minimising drops where possible.
Growers have been reminded that settings on the harvester may have to be changed or adjusted for soil conditions and different varieties.
Teagasc has also issued advisory guidelines to help growers maximise their saleable yields of potatoes this year.
Operators should ensure the diablo rollers on the harvester are aligned with the drills. Avoidance of too much downward pressure is critical, as this will squash tubers near the surface.
It is important during wet conditions, to avoid bulldozing the drills or bruising tubers near the surface.
Share depths
Share depths should be checked e.g. too shallow and tubers will be sliced, too deep and extra soil will be brought onto the web. This will need extra separation which will slow down the operation.
Disc settings should also be checked. If it is too wide, then growers risk bringing extra soil and even stones onto the webs, too deep and again tubers may be sliced.
Operators should aim to have the sieving web set at 85% filled with tubers. If the web is too slow, then growers risk tubers being forced to the side and damaged. If the setting is too fast, tubers will roll back down the web.
It is important to keep agitation of the tubers to the minimum level required to remove soil.
Bouncing the tubers will cause excessive bruising. Many crops are reported to have high dry matters this year and so they are particularly vulnerable in this regard.
Roller speed
The speed of the rollers on the harvester should also be assessed. If they are turning too fast, they can throw tubers up in the air; too slow and they can ‘grab’ the tubers.
It is important to watch out for wear on all padding material and side curtains, where gaps appear tubers can get trapped or banged.
When transferring potatoes to the trailer or box, operators should make sure there is good communication between the drivers.
The fall of the tubers should be cushioned as much as possible.
Dropping tubers from a height of more than 1m onto a hard floor will result in bruising. What’s more, dropping a tuber more than 1m onto another tuber will damage both.
Writer: Richard Halleron
