Many growers might think that oilseed rape, with its long tap root, is an answer to the problems caused by soil compaction.
However, according to Teagasc research scientist, Dermot Forristal, the polar opposite is the case.
He explained: “Oilseed rape does not tolerate compacted ground conditions. In such instances, the tap root may well start veering off to the left or right, once it encounters a compacted soil layer.
“The end result in these circumstances is a significant reduction in yield.
“The way to avoid this happening is to plan ahead and to employ establishment systems that actually ease compaction problems. Field headlands are areas where compaction issues are most likely to arise.”
Oilseed rape
Forristal was speaking on the most recent edition of the Tillage Edge podcast.
He was joined by Teagasc tllage specialist Shay Phelan, who confirmed that oilseed rape can be a very delicate crop, particularly during its first weeks of growth.
“Oilseed rape is very predisposed to pest attack during a crop’s establishment phase,” Phelan further explained.
“In the first instance, farmers should be looking out for slugs. Field history is also a very important factor in this regard.”
Pest management
The tillage specialist is mindful of the need for farmers to use an integrated pest management approach to slug control – in the first instance.
He explained:
“Prior to sowing, growers should put some slug traps in order to gauge how big a potential problem there might be. But in cases where the issue is likely to cause real problems, the option of putting out slug pellets with the seed at planting can be considered.
The other pest-related problem that gets a lot of air play, particularly in the UK, is cabbage stem flea beetle.
“The matter has become such an issue in the UK that some growers have given up growing the crop for that reason,” said Phelan.
The beetles bore a hole in the cotyledon of the growing OSR plant. They can then go on to decimate a crop, especially in dry conditions.
Because damper weather tends to predominate at time of sowing on this side of the Irish Sea, cabbage stem flea beetle tends to be less of a problem in Ireland.
“Pigeon grazing can be a real problem, particularly in late planted rape crops,” Shay Phelan added however.
“It has been known for pigeons to pull September oilseed rape plants directly out of the ground. This is because they are less well established and growth has very much stopped by that time of the year.”
