Robert
Member
- Location
- South East
We have planted over wintered cover crops for the last 2 winters, followed by spring oats and linseed. Have seen really pleasing biomass produced and have mainly grazed this off with sheep. i think the whole concept of maintaining growing crops for the soil biology to interact with, soil moisture management, soil structuring via rooting etc quite logical / convincing but some results this season suggest that careful management of grazing to avoid surface compaction / tilth loss is very important to the extent that if you breach a certain level of over grazing as we seem to have done this year, i think we'd have been better off just leaving the stubble over winter.
We have some excellent looking S Oats on land intended for winter wheat which we consequently didn't drill a cover crop on after harvest. The Oats follow linseed admitedly so it should be a very kind environment - and they are thriving. S Oats after grazed cover crop after wheat are a fair bit thinner mainly due to poorer establishment brought about by poor tilth creation and therefore seed to soil contact. I am fairly happy that the grazing compaction is very much in the surface so i believe the pooer growth is due to a poorer start rather than general impediment as the roots have got going. We have spring barley after s oats where it was left as pure stubble and they have got away nicely.
I think that all in all it perhaps highlights the extra management required in the process and having to consider things on a field by field basis. Not having direct control of the sheep doesn't help, and every season is different: amount of wet, amount of frost heave before drilling etc...
We really need to do more trial work on this to get an idea of effect on yield. The crop growth results we're seeing this year though just pose the question of overall - are the cover crops really necessary. The Wheat / Fallow brigade often seem to manage well without so why hasn't their soil biology suffered? Dockers??! Perhaps one extreme or the other is sensible - i get the impression that constant max cover (no grazing) has real merit.
p.s. Drill = Claydon Hybrid
We have some excellent looking S Oats on land intended for winter wheat which we consequently didn't drill a cover crop on after harvest. The Oats follow linseed admitedly so it should be a very kind environment - and they are thriving. S Oats after grazed cover crop after wheat are a fair bit thinner mainly due to poorer establishment brought about by poor tilth creation and therefore seed to soil contact. I am fairly happy that the grazing compaction is very much in the surface so i believe the pooer growth is due to a poorer start rather than general impediment as the roots have got going. We have spring barley after s oats where it was left as pure stubble and they have got away nicely.
I think that all in all it perhaps highlights the extra management required in the process and having to consider things on a field by field basis. Not having direct control of the sheep doesn't help, and every season is different: amount of wet, amount of frost heave before drilling etc...
We really need to do more trial work on this to get an idea of effect on yield. The crop growth results we're seeing this year though just pose the question of overall - are the cover crops really necessary. The Wheat / Fallow brigade often seem to manage well without so why hasn't their soil biology suffered? Dockers??! Perhaps one extreme or the other is sensible - i get the impression that constant max cover (no grazing) has real merit.
p.s. Drill = Claydon Hybrid