The past couple of months have seen extremely low amounts of rainfall in the South, which has been good for getting spring crops in the ground, but dry seedbeds have caused some issues
We have experienced less-than-adequate weed control from pre-ems, what rain we did have came too late to reactivate the residuals so many spring bean crops received a follow up of bentazone to tackle any charlock and a graminicide for controlling black-grass, which had appeared in significant numbers.
Spring barley also experienced the same problem, which had again caused large populations of black-grass to appear in places. Late-drilled crops sat in dry seedbeds waiting for a drop of rain to get going, but once up, quickly caught up with the rest, as early sowings had been held back by the cold soils.
The warm dry weather has also seen a surge in the level of insect pests. In a rare instances, seed weevil in oilseed rape exceeded thresholds so had to be sprayed separately to fungicide applications, but generally the cold nights kept populations to a minimum and Mavrik was included at petal fall for any crops which still had populations present above threshold with the mid-flowering fungicide.
Pea and bean weevil in pulses and flea beetle in linseed and fodder crops caused some damage at emergence, so all crops have had at least one insecticide, many have had two where damage has held the crop back or where emergence was patchy. Some bean rust had crept in the start of May on winter beans, otherwise disease levels in beans have remained low. We are still looking out for downy mildew in spring beans, which will be treated as soon as infection is seen with a phosphite, which will provide protection rather than eradication. Winter bean crops have had both fungicides, which have been chlorothalanil and triazole-based for protection against chocolate spot and bean rust, and spring beans have had one application with a second being planned in if disease levels are high.
T2 applications are going on winter barley and wheat. Disease levels so far have been low, and growth rapid, so the gap between T1 and T2 has been no more than three weeks on both the wheat and barley.
Maize all went into warm seedbeds with plenty of moisture and are moving rapidly. Pre-emergence applications of pendimethalin gave the crop a good start with weed control as soils were moist at application and we will be planning in a follow-up herbicide depending on weeds present at the time as soon as crops are through the ground.
Broad-leaved weed and wild oat control has now all been dealt with as well as growth regulation, leaving T3 applications left to be planned for early June and in some cases end of May. These will likely to be based around tebuconazole and prothioconazole for “normal” or backward crops and possibly Amistar Opti (azoxystrobin+chlorothalonil) on the more forward crops if weather is wet during flowering or if fusarium infections are looking likely, especially where maize was grown previously. It may be a good idea to add in straight chlorothalanil at T3 if not using Amistar Opti to keep septoria protection topped up especially on susceptible varieties such as Gallant and Solstice or if chlorothalanil wasn’t used at T2.