Rainfall over the past couple of weeks has been localised, with heavy showers for some and nothing elsewhere. The Severn Vale had just 7.5mm of rain in March and nothing so far in April. In the drier areas, particularly on thin brash soils, crop growth has slowed.
More forward crops of wheat are approaching T1 timing, the fungicide and growth regulator being applied once leaf 3 is 75 per cent emerged. Fungicide choice should be based on varietal susceptibilities to disease.
Mildew, a problem earlier in the year, seems to have been left behind and the main worries now are septoria and rusts. So far I have found rust only in Claire, which showed strange symptoms, only the tips of the leaves being affected. It is also worth checking for eyespot as there are fairly high levels in some second wheat crops.
Broad-leaved weeds will be taken care of at the same time as the T1 spray is applied, but any spring-germinating blackgrass will have to be left alone where Atlantis (iodosulfuron + mesosulfuron) was used earlier. Wild oats are still emerging so they will need to be treated later.
Oilseed rape crops have come into flower in the past week. Late crops are still at risk from pollen beetle until they start to flower. When deciding whether to spray, note that later, thinner crops have a lower threshold of five beetles per main stem. For rape crops still at green/yellow bud stage there is still time to apply a growth regulating fungicide, if deemed necessary by the Green Area Index. More developed crops of rape will shortly get their final nitrogen, otherwise they will be too tall for accurate application.
Spring beans have got off to a good start but are being attacked by weevil. Check for the characteristic notching around the leaf margins and spray if found. The main damage is caused by the weevil larvae feeding on the nitrogen-fixing root nodules, so it is important to control the adult weevil before they lay eggs. It is often necessary to spray twice, a couple of weeks apart.
Spring oilseed rape and linseed are beginning to emerge and need to be monitored frequently for flea beetle, even where they have a preventative seed dressing. Check the game cover crops too, where they contain susceptible plants.