Crop Watch: Winds cause complete OSR crop failure
The cold easterly winds have caused more crop failure this week, as already stressed oilseed rape crops are made to suffer further.
After a relatively kind February, March has seen a cold spell that has halted crop growth and spring fieldwork and Devon agronomist Neil Potts has seen instances of severe crop scorch.
“The oilseed rape has been particularly badly affected. There are a few fields where the crop has finally given up,” he says.
It is a similar story in Yorkshire, particularly along the east coast where David Martindale’s crops are also being pushed to the brink by the relentless easterly winds.
Despite the problematic weather he notes that there is still no sign of yellow rust, even in the susceptible varieties such as Oakley and Torch, but reminds growers they must be on the lookout.
“It’s a case of when, and not if, it appears. The cold weather should allow us to reach the T0 timing for yellow rust control without bringing forward the T1 fungicide,” says Mr Martindale.
In the south, AICC agronomist Tod Hunnisett doesn’t believe many of his wheat crops will receive a T0 fungicide or a normal plant growth regulator regime.
He estimates that just 25% of his winter wheat will have the early, holding fungicide treatment and prefers to wait and apply a standard T1 with chlormequat and some herbicide.
“I have many crops where inputs will have to be managed accordingly on the assumption that yield potential will be much lower than usual. Perhaps later drilled wheat will only have two fungicides,” says Mr Hunnisett.
Herbicide headache
Of concern to eastern agronomist Philip Vickers this week is the volume of winter crops that have not received an autumn herbicide. Contact graminicides such as Atlantis (iodosulfuron + mesosulfuron) and Unite (flupyrsulfuron + pyroxsulam) are the only options when blackgrass is the target in winter wheat.
He urges growers, where using these products this spring, to ensure the efficacy is maximised by correct application in the correct conditions and with weeds actively growing.
High disease risk varieties will also be requiring a fungicide, he says, so it will be important to check tank mix compatibility when adding to the contact graminicides.
“Hopefully we can avoid having to apply the T0 at the same time, but we need to keep our options open.
“We often get late germinating wild oats after a cold spring, so if this is likely to be the case we should hold off with the graminicides as long as possible,” explains Mr Vickers.
Oilseed rape may still require a herbicide treatment and Mr Potts warns that attention will have to be paid to growth stages, as crop development is likely to be rapid when the temperatures rise.
“Most backward rape crops have had a large dose of nitrogen, so when growth starts growers will need to be vigilant to catch the right crops stage for applications of Galera (clopyralid + picloram),” he says.
Spud season starts
First earlies have been planted in Cheshire and wrapped up under fleece says independent potato agronomist John Sarup, but the field work has since halted in the cold and wet weather.
He urges growers that have been delayed with seed in the shed to decant it from bags into boxes where possible, allowing for ventilation and inspection to ensure quality is maintained.
“The fundamentals of potato growing are cultivations and seed. This spring I have concerns about both,” he says.
“There is only a limited time to register complaints with seed suppliers if there are any quality issues. Once the seed is in the planter it is probably too late.”
Cultivations will be challenging, he continues, with soil conditions largely remaining wet across the country. He is urging flexibility in approach this year.
Subsoiling will be a non-starter as lift and shatter will be minimal, so a ridged tine to open soils and aerate at depth may be advisable.
“Subsequent operations will need to be timely to avoid the ground drying out too much,” he says.
