With this prolonged period of wet weather, sprayers have remained in sheds for at least two weeks, and the job list is still getting longer.
First priority will be insecticide applications on winter cereals. For some fields this will be the first since drilling, for others this will be the third application. Hopefully winter will kick in and further applications won’t be needed (I know I said the same thing four weeks ago), but until there is a prolonged spell of frosty weather there is potential for aphids to breed and move, therefore increasing the risk of barley yellow dwarf virus (BYDV) infections.
Pre-emergence herbicide sprays worked well, so there are fewer than usual fields that need, or have had, Atlantis, Unite or Broadway Star applications. Those that are still waiting to go on need to be applied as soon as possible, as once plants shut down for the winter control levels will drop off. There are some barley fields that will need Axial (pinoxaden) for blackgrass control and hopefully it will be small enough to get a good kill. As with wheat, 1-2 leaf of blackgrass is the ideal timing for post-emergence applications.
The big surprise of the autumn has been the levels of phoma around. Differences in varieties disease ratings are standing out. Those with an 8 or 9 are still at about 1-2% infection. As ratings drop off, so the level of phoma is getting higher. I do have a couple of blocks that are at 20-25% infection, so are at the top of the hit list.
Most crops, including those drilled well into September, are strong with plants carrying 8+ leaves, so can stand phoma and light leaf spot sprays that have a plant growth regulation (PGR) effect. Both Monkey (tebuconazole + prochloraz) and Frelizon (penthiopyrad + picoxystrobin) give good control and protection of both diseases so are good options.
Where either Kerb (propyzamide) or Crawler (carbetamide) are needed for grassweed control, these will be mixed with a fungicide once weather allows a sprayer to travel. As with most things in life there will be compromise – fungicides want a dry leaf at application, but Kerb and Crawler can cope with a wet leaf, as we want them to run off leaves and hit the soil. Spray days will be limited, so we won’t get conditions right for both.