Crop watch: Wet curbs drilling – Farmers Weekly – Ben Pledger
Ben Pledger looks at agronomic issues in the East (Bedfordshire/Hertfordshire) ...
Although we had good drying weather towards the end of last week, which allowed more drilling on light to medium soils, the heavier clays were just about dry enough to think about getting close to with a drill – and then it rained again.
More cereal crops than usual are showing effects of bleaching from the pre-emergence herbicides applied, with those having been treated with diflufenican showing the greatest symptoms. This is mainly due to crops swimming in wet soils, with the pre-emergence chemistry sitting in solution around them.
There are now murmurings on farm about getting the fertiliser spreader out and spinning cereals on and harrowing them in as a means of establishment.
There are a couple of issues associated with this that could potentially seriously limit yield:
Firstly, by going down this ledger route, the soil will be wet and must be treated with respect. Fields established like this last year and then power-harrowed in saw the tips of the power harrow smear a pan that not only held water in the top few inches of soil, but impeded the downward movement of roots. So when it dried up in the spring, the ability for crops to access moisture was limited. Choice of cultivation implement will play a large part in maintaining yield potential.
Secondly, spinning cereals on will limit your residual chemistry options －no manufacturer will support pre-emergence application of their chemistry onto broadcast crops, leaving only post-emergence residual control as an option.
Big and strong enough
The plant will need to be big enough and strong enough to accept this application, and I would advise not applying before the crop gets to the two-leaf stage (growth stage 12).
You will also need to keep in mind that some residual herbicides do not have approval for post-emergence application, namely tri-allate and aclonifen, so some planned pre-emergence applications cannot just be applied post emergence.
Hopefully, by the time l write next, the weather will have given you the break you’re after…