East: Flea beetles are an active threat

The 22.6mm of rain we had at the beginning of September has completely disappeared, and some of the later emerging oilseed rape on heavy land looks in need of a drink. However I will not tempt fate by saying we need some.

Where rape has been established in the conventional way it has all been treated pre-emergence with the first dose of herbicide. My preferred product choice has been Shadow or Katamaran Turbo (dimethanamid-P + metazachlor + quinmerac), as it worked exceptionally well last year.

Rape crops established via the sub-soiler technique that are at the fully expanded cotyledon stage are about to be treated post-emergence in mix with a graminicide. Product choice depends on whether blackgrass is present.

With such dry conditions, there is very little evidence of slug activity. Where headlands have been treated I have recommended ferrous phosphate based products.

The pest that is active is flea beetle. It shows the advantage of usinga seed treatment with good activity against it, as any germinatinguntreated seed would have been bitten off below ground level. At leastthe seed dressings have allowed the crop to emerge and get to fullyexpanded cotyledon and beyond stage.

Winter wheat drilling has started but only on fields that do not haveserious grassweed infestations. Where blackgrass is a problem fieldsshould be drilled later to allow any germinating blackgrass to betreated with glyphosate pre-drilling.

Seed rates on these fields should also be kept up. I always remindgrowers it is easier to manage a thick crop than a thin one. I am alsoreminding growers that in order to get the best performance frompre-emergence herbicides they need to create good seed-beds with tilth,which in some cases on heavy land may prove difficult. The three thingsto remember are drill, roll, spray.

We can no longer rely on Atlantis (mesosulfuron-methyl +iodosulfuron-methyl-sodium) as the final solution to blackgrasscontrol, but it is part of an integrated programme. I am waiting withinterest for the results of the blackgrass samples that I sent forresistance testing in mid-July. My bet is that at least half will showresistance to Atlantis.

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