Taken from Agronomist & Arable Farming, March 2017, written by Rob Purvis
Oilseed rape crops vary in my corner of England, from good robust stands with full ground cover to those with three to four leaves and low plant numbers. The main reason for this range of crop growth has been the amount of rain they received to get them away during establishment.
With rape prices as they are, look carefully before abandoning crops. Fields with as few as six plants per square metre can produce respectable yields, if managed correctly and weed control is good.
The window for grass weed control with Crawler closed at the end of February, but now we are into March, broadleaved weed control with clopyralid containing products can take place.
Smaller crops will need more nitrogen early in the programme to get them to a green area index of 3.5 at flowering.
Winter wheats seem to be faring well and in general look to have good potential. Septoria can easily be found on the older leaves, but the recent cold snap has held the rusts back in our South East corner.
I will monitor rust very carefully at TO and include a rust-active triazole or strobilurin with CTL, where necessary. Last year, there were pustules of brown rust on Crusoe at TO - these can easily be missed and come back to bite you.
Unless someone can produce a crystal ball to forecast the weather, I will encourage my clients to use an SDHI at Tl. If the programme goes wrong at this timing, there is no chemistry that will put it right at T2 in a high disease-pressure year.
I am currently recommending glyphosate applications to destroy cover crops, prior to direct drilling spring barley or spring wheat. Some thicker cover crops will require an initial spray to open them up and a follow-up to make sure that any black-grass below them is killed.
Nitrogen rates on spring malting barley will have to be fine-tuned to make sure that the grain N specified on contracts are not exceeded. I fear that there will be a great difference between the malting and feed price, while the price differential between feed and milling spring wheat will not be so much, so this may be a lower risk crop.
Where cover crops have established well, the fields are walking very well and the soil is in excellent condition, I will encourage my growers to drill into them with as little disturbance as possible to discourage black-grass germination.
Even small points that help reduce soil disturbance, such as reducing tractor tyre pressures, will help.
I will aim for wheat seed rates of 550 seeds/sq m and barley seed rates of 450/sq m with this drilling technique. Some cover crops have been sprayed off for well over a month and I expect following crops to get off to a quicker start as the green matter has had longer to break down and will have begun to release nitrogen.